Anti-reflective layer and method

ABSTRACT

A system and method for anti-reflective layers is provided. In an embodiment the anti-reflective layer comprises a floating component in order to form a floating region along a top surface of the anti-reflective layer after the anti-reflective layer has dispersed. The floating component may be a floating cross-linking agent, a floating polymer resin, or a floating catalyst. The floating cross-linking agent, the floating polymer resin, or the floating catalyst may comprise a fluorine atom.

CROSS REFERENCE

This application is a continuation and claims the benefit of U.S. patentapplication Ser. No. 14/056,737 filed on Oct. 17, 2013, entitled“Anti-Reflective Layer and Method,” which claims the benefit of U.S.Provisional Application No. 61/777,782 filed on Mar. 12, 2013, entitled“Anti-Reflective Layer and Method,” which applications are herebyincorporated herein by reference.

BACKGROUND

As consumer devices have gotten smaller and smaller in response toconsumer demand, the individual components of these devices havenecessarily decreased in size as well. Semiconductor devices, which makeup a major component of devices such as mobile phones, computer tablets,and the like, have been pressured to become smaller and smaller, with acorresponding pressure on the individual devices (e.g., transistors,resistors, capacitors, etc.) within the semiconductor devices to also bereduced in size.

One enabling technology that is used in the manufacturing processes ofsemiconductor devices is the use of photolithographic materials. Suchmaterials are applied to a surface and then exposed to an energy thathas itself been patterned. Such an exposure modifies the chemical andphysical properties of the exposed regions of the photolithographicmaterial. This modification, along with the lack of modification inregions of the photolithographic material that were not exposed, can beexploited to remove one region without removing the other.

However, as the size of individual devices has decreased, processwindows for photolithographic processing as become tighter and tighter.As such, advances in the field of photolithographic processing, such asthe use of anti-reflective layers to prevent undesired reflections ofimpinging light, have been necessitated in order to keep up the abilityto scale down the devices, and further improvements are needed in orderto meet the desired design criteria such that the march towards smallerand smaller components may be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present embodiments, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates an initial dispersion of a bottom anti-reflectivelayer on a semiconductor substrate in accordance with an embodiment;

FIG. 2 illustrates a formation of a floating region in accordance withan embodiment;

FIG. 3 illustrates a baking process in accordance with an embodiment;

FIGS. 4A-4B illustrate an application, exposure, and development of aphotoresist in accordance with an embodiment; and

FIG. 5 illustrates another embodiment in which the bottomanti-reflective coating is planarized in a chemical mechanical polishingprocess in accordance with an embodiment.

Corresponding numerals and symbols in the different figures generallyrefer to corresponding parts unless otherwise indicated. The figures aredrawn to clearly illustrate the relevant aspects of the embodiments andare not necessarily drawn to scale.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The making and using of the present embodiments are discussed in detailbelow. It should be appreciated, however, that the present disclosureprovides many applicable inventive concepts that can be embodied in awide variety of specific contexts. The specific embodiments discussedare merely illustrative of specific ways to make and use the disclosedsubject matter, and do not limit the scope of the different embodiments.

Embodiments will be described with respect to a specific context, namelya bottom anti-reflective coating utilized in the manufacturing ofsemiconductor devices. Other embodiments may also be applied, however,to other coatings in different processes.

With reference now to FIG. 1, there is shown a substrate 101 with fins103 formed over the substrate 101 and a bottom anti-reflective coating(BARC) layer 105 applied over the fins 103 and the substrate 101. Thesubstrate 101 may comprise bulk silicon, doped or undoped, or an activelayer of a silicon-on-insulator (SOI) substrate. Generally, an SOIsubstrate comprises a layer of a semiconductor material such as silicon,germanium, silicon germanium, SOI, silicon germanium on insulator(SGOI), or combinations thereof. Other substrates that may be usedinclude multi-layered substrates, gradient substrates, or hybridorientation substrates.

The fins 103 will serve as a fin structure for the eventual formation ofFinFET or multiple gate transistors (not separately illustrated in FIG.1). In an embodiment the fins 103 may be formed from the material of thesubstrate 101 and, as such, may also comprise bulk silicon, doped orundoped, or be an active layer of a SOI substrate. The fins 103 may beformed by first applying a masking material over the substrate 101,patterning the masking material, and then using the masking material asa mask to etch into the substrate 101, thereby forming the fins 103 fromthe material of the substrate 101.

However, using the material of the substrate 101 to form the fins 103 isonly one illustrative method that may be used to form the fins 103.Alternatively, the fins 103 may be formed by initially depositing asemiconductor material, such as silicon, silicon-germanium, or the like,over the substrate 101 and then masking and etching the semiconductormaterial to form the fins 103 over the substrate 101. In yet anotheralternative, the fins 103 may be formed by masking the substrate 101 andusing, e.g., an epitaxial growth process to grow the fins 103 on thesubstrate 101. These, and any other suitable method for forming the fins103 may alternatively be utilized, and all such methods are fullyintended to be included within the scope of the embodiments.

The BARC layer 105 is applied over the fins 103 and fills the regionsbetween the fins 103 in preparation for an application of a photoresist401 (not illustrated in FIG. 1 but illustrated and described below withrespect to FIG. 4A). The BARC layer 105, as its name suggests, works toprevent the uncontrolled and undesired reflection of energy (e.g.,light) such as light back into the overlying photoresist 401 during anexposure of the photoresist 401, thereby preventing the reflecting lightfrom causing reactions in an undesired region of the photoresist 401.Additionally, the BARC layer 105 may be used to provide a planar surfaceover the substrate 101 and the fins 103, helping to reduce the negativeeffects of the energy impinging at an angle.

In an embodiment the BARC layer 105 comprises a polymer resin, acatalyst, and a cross-linking agent, all of which are placed into asolvent for dispersal. The polymer resin may comprise a polymer withvarious monomers bonded together. In an embodiment the polymer maycomprise different monomers such as a cross-linking monomer and amonomer with chromophore units. In an embodiment the monomer with thechromophore unit may comprise vinyl compounds containing substituted andunsubstituted phenyl, substituted and unsubstituted anthracyl,substituted and unsubstituted phenanthryl, substituted and unsubstitutednaphthyl, substituted and unsubstituted acridine, substituted andunsubstituted quinolinyl and ring-substituted quinolinyls (e.g.,hydroxyquinolinyl), substituted and unsubstituted heterocyclic ringscontaining heteroatoms such as oxygen, nitrogen, sulfur, or combinationsthereof, such as pyrrolidinyl, pyranyl, piperidinyl, acridinyl,quinolinyl. The substituents in these units may be any hydrocarbyl groupand may further contain heteroatoms, such as, oxygen, nitrogen, sulfuror combinations thereof, such as alkylenes, esters, ethers, combinationsof these, or the like, with carbon atoms between 1 and 12.

In specific embodiments the monomers with chromophore units includestyrene, hydroxystyrene, acetoxystyrene, vinyl benzoate, vinyl4-tert-butylbenzoate, ethylene glycol phenyl ether acrylate,phenoxypropyl acrylate, N-methyl maleimide,2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate, 2-hydroxy-3-phenoxypropylacrylate, phenyl methacrylate, benzyl methacrylate, 9-anthracenylmethylmethacrylate, 9-vinylanthracene, 2-vinylnaphthalene, N-vinylphthalimide,N-(3-hydroxy)phenyl methacrylamide,N-(3-hydroxy-4-hydroxycarbonylphenylazo)phenyl methacrylamide,N-(3-hydroxyl-4-ethoxycarbonylphenylazo)phenyl methacrylamide,N-(2,4-dinitrophenylamino phenyl)maleimide,3-(4-acetoaminophenyl)azo-4-hydroxystyrene,3-(4-ethoxycarbonylphenyl)azo-acetoacetoxy ethyl methacrylate,3-(4-hydroxyphenyl)azo-acetoacetoxy ethyl methacrylate,tetrahydroammonium sulfate salt of 3-(4-sulfophenyl)azoacetoacetoxyethyl methacrylate combinations of these, or the like. However, anysuitable monomer with chromophore units to absorb the impinging lightand prevent the light from being reflected may alternatively be used,and all such monomers are fully intended to be included within the scopeof the embodiments.

The cross-linking monomer may be used to cross-link the monomer withother polymers within the polymer resin, to modify the solubility of theBARC layer 105, and may optionally have an acid labile group. In aparticular embodiment the cross-linking monomer may comprise ahydrocarbon chain that also comprises, e.g., a hydroxyl group, acarboxyl acid group, a carboxylic ester group, epoxy groups, urethanegroups, amide groups, combinations of the, and the like. Specificexamples of cross-linking monomers that may be utilized includepolyhydroxystyrene, poly(hydroxynaphthalene), poly(meth)acrylates,polyarylates, polyesters, polyurethanes, alkyd resins(aliphaticpolyesters), poly(hydroxystyrene-methylmethacrylate), homopolymersand/or copolymers obtained by polymerization of at least one of thefollowing monomers: styrene, hydroxystyrene, hydroxyethyl(meth)acrylate,hydroxypropyl(meth)acrylate, methyl(meth)acrylate, ethyl(meth)acrylate,(meth)acrylic acid, poly(hydroxystyrene-styrene-methacrylate),poly(4-hydroxystyrene), and poly(pyromellitic dianhydride-ethyleneglycol-propylene oxide).

The various monomers will be polymerized with one another to form apolymer structure with a carbon chain backbone for the polymer resin. Inan embodiment the polymer structure may have a carbon chain backbonethat is an acrylic, a polyester, an epoxy novalac, a polysaccharide, apolyether, a polyimide, a polyurethane, and mixtures thereof. Oneexample of a particular polymer resin that may be utilized has thefollowing structure:

where each R and R¹ may be a hydrogen or a substituted or unsubstitutedalkyl group having from 1 to 8 carbon atoms; each R² may be asubstituted or unsubstituted alkyl having from 1 to 10 carbon atoms; andeach R³ may be a halogen atom, an alkyl having from 1 to 8 carbon atoms,an alkoxy having between 1 to 8 carbon atoms, an alkenyl having between2 to 8 carbon atoms, an alkynyl having from 2 to 8 carbon atoms, cyano,nitro; m is an integer of from 0 to 9; and x is the mole fraction ofpercent of alkyl units in the polymer resin and is between about 10% andabout 80%; and y is the mole fraction or percent of anthracene units inthe polymer resin and is between about 5% and about 90%.

Additionally, as one of ordinary skill in the art will recognize, theabove description for the various monomers that may be polymerized toform the polymer resin for the BARC layer 105 are intended to beillustrative and are not intended to limit the embodiments in anyfashion. Rather, any suitable monomer or combination of monomers thatperform the desired functions of the monomers described herein may alsobe utilized. All such monomers are fully intended to be included withinthe scope of the embodiments.

The catalyst may be a compound that is used to initiate a cross-linkingreaction between the polymers within the polymer resin, and may be,e.g., a thermal acid generator, a photoacid generator, a photobasegenerator, suitable combinations of these, or the like. In an embodimentin which the catalyst is a thermal acid generator, the catalyst willgenerate an acid when sufficient heat is applied to the BARC layer 105.Specific examples of the thermal acid generator include butane sulfonicacid, triflic acid, nonaflurobutane sulfonic acid, nitrobenzyltosylates, such as 2-nitrobenzyl tosylate, 2,4-dinitrobenzyl tosylate,2,6-dinitrobenzyl tosylate, 4-nitrobenzyl tosylate; benzenesulfonatessuch as 2-trifluoromethyl-6-nitrobenzyl 4-chlorobenzenesulfonate,2-trifluoromethyl-6-nitrobenzyl 4-nitro benzenesulfonate; phenolicsulfonate esters such as phenyl, 4-methoxybenzenesulfonate; alkylammonium salts of organic acids, such as triethylammonium salt of10-camphorsulfonic acid, combinations of these, or the like.

In an embodiment in which the catalyst is a photoacid generator, thecatalyst may comprise halogenated triazines, onium salts, diazoniumsalts, aromatic diazonium salts, phosphonium salts, sulfonium salts,iodonium salts, imide sulfonate, oxime sulfonate, disulfone,o-nitrobenzylsulfonate, sulfonated esters, halogenerated sulfonyloxydicarboximides, diazodisulfones, α-cyanooxyamine-sulfonates,imidesulfonates, ketodiazosulfones, sulfonyldiazoesters,1,2-di(arylsulfonyl)hydrazines, nitrobenzyl esters, and the s-triazinederivatives, suitable combinations of these, and the like.

Specific examples of photoacid generators that may be used includeα-(trifluoromethylsulfonyloxy)-bicyclo[2.2.1]hept-5-ene-2,3-dicarbo-ximide(MDT), N-hydroxy-naphthalimide (DDSN), benzoin tosylate,t-butylphenyl-α-(p-toluenesulfonyloxy)-acetate andt-butyl-α-(p-toluenesulfonyloxy)-acetate, triarylsulfonium anddiaryliodonium hexafluoroantimonates, hexafluoroarsenates,trifluoromethanesulfonates, iodonium perfluorooctanesulfonate,N-camphorsulfonyloxynaphthalimide,N-pentafluorophenylsulfonyloxynaphthalimide, ionic iodonium sulfonatessuch as diaryl iodonium (alkyl or aryl) sulfonate andbis-(di-t-butylphenyl)iodonium camphanylsulfonate,perfluoroalkanesulfonates such as perfluoropentanesulfonate,perfluorooctanesulfonate, perfluoromethanesulfonate, aryl (e.g., phenylor benzyl) triflates such as triphenylsulfonium triflate orbis-(t-butylphenyl)iodonium triflate; pyrogallol derivatives (e.g.,trimesylate of pyrogallol), trifluoromethanesulfonate esters ofhydroxyimides, α,α′-bis-sulfonyl-diazomethanes, sulfonate esters ofnitro-substituted benzyl alcohols, naphthoquinone-4-diazides, alkyldisulfones, and the like.

In other embodiment the catalyst may be a photobase generator. In suchan embodiment the photobase generator may comprise quaternary ammoniumdithiocarbamates, a aminoketones, oxime-urethane containing moleculessuch as dibenzophenoneoxime hexamethylene diurethan, ammoniumtetraorganylborate salts, and N-(2-nitrobenzyloxycarbonyl) cyclicamines, suitable combinations of these, or the like.

In an embodiment the floating cross-linking agent is also included withthe polymer resin and the catalyst. The floating cross-linking agentwill react with the polymers within the polymer resin and form linear orbranched polymers structure that have larger molecular weight molecules,thereby improving the cross-linking density. In an embodiment thefloating cross-linking agent may be an aliphatic polyether such as apolyether polyol, a polyglycidy ether, a vinyl ether, a glycouril, atriazene, combinations of these, or the like.

In an embodiment in which the floating cross-linking agent is apolyether polyol, the floating cross-linking agent has the followingstructure:

where n¹ represents an integer of 1 to 300; m¹ represents an integer of2 to 6; R⁴ represents a hydrogen atom or an alkyl group having 1 to 10carbons atom(s); and R⁵ represents an alkyl group having 1 to 10 carbonatom(s), an alkenyl group having 2 to 6 carbon atoms, an alkynyl grouphaving 2 to 10 carbon atoms, alkylcarbonyl group having 2 to 10 carbonatoms, an alkylcarbonylamino group having 2 to 10 carbon atoms, analkyloxyalkyl group having 2 to 10 carbon atoms, an alkylamino grouphaving 1 to 10 carbon atom(s), an alkyldiamino group having 1 to 10carbon atom(s) or a combination thereof and is an organic group capableof having a valence number of 2 to 6 according to the number m ofpolyoxyalkylene groups. Specific examples of alkyl groups that may beused for R⁴ include methyl group, an ethyl group, a propyl group, anisopropyl group, an n-butyl group and an n-pentyl group.

Specific examples of an alkyl group that may be used for R⁵ includemethyl group, an ethyl group, an n-propyl group, an isopropyl group, acyclopropyl group, an n-butyl group, an isobutyl group, an s-butylgroup, a tert-butyl group, a cyclobutyl group, a 1-methyl-cyclopropylgroup, a 2-methyl-cyclopropyl group, an n-pentyl group, a1-methyl-n-butyl group, a 2-methyl-n-butyl group, a 3-methyl-n-butylgroup, a 1,1-dimethyl-n-propyl group, a 1,2-dimethyl-n-propyl group, a2,2-dimethyl-n-propyl group, a 1-ethyl-n-propyl group, a cyclopentylgroup, a 1-methyl-cyclobutyl group, a 2-methyl-cyclobutyl group, a3-methyl-cyclobutyl group, a 1,2-dimethyl-cyclopropyl group, a2,3-dimethyl-cyclopropyl group, a 1-ethyl-cyclopropyl group, a2-ethyl-cyclopropyl group, an n-hexyl group, a 1-methyl-n-pentyl group,a 2-methyl-n-pentyl group, a 3-methyl-n-pentyl group, a4-methyl-n-pentyl group, a 1,1-dimethyl-n-butyl group, a1,2-dimethyl-n-butyl group, a 1,3-dimethyl-n-butyl group, a2,2-dimethyl-n-butyl group, a 2,3-dimethyl-n-butyl group, a3,3-dimethyl-n-butyl group, a 1-ethyl-n-butyl group, a 2-ethyl-n-butylgroup, a 1,1,2-trimethyl-n-propyl group, a 1,2,2-trimethyl-n-propylgroup, a 1-ethyl-1-methyl-n-propyl group, a 1-ethyl-2-methyl-n-propylgroup, a cyclohexyl group, a 1,4-dimethyl-cyclohexyl group, a1-methyl-cyclopentyl group, a 2-methyl-cyclopentyl group, a3-methyl-cyclopentyl group, a 1-ethyl-cyclobutyl group, a2-ethyl-cyclobutyl group, a 3-ethyl-cyclobutyl group, a1,2-dimethyl-cyclobutyl group, a 1,3-dimethyl-cyclobutyl group, a2,2-dimethyl-cyclobutyl group, a 2,3-dimethyl-cyclobutyl group, a2,4-dimethyl-cyclobutyl group, a 3,3-dimethyl-cyclobutyl group, a1-n-propyl-cyclopropyl group, a 2-n-propyl-cyclopropyl group, a1-isopropyl-cyclopropyl group, a 2-isopropyl-cyclopropyl group, a1,2,2-trimethyl-cyclopropyl group, a 1,2,3-trimethyl-cyclopropyl group,a 2,2,3-trimethyl-cyclopropyl group, a 1-ethyl-2-methyl-cyclopropylgroup, a 2-ethyl-1-methyl-cyclopropyl group, a2-ethyl-2-methyl-cyclopropyl group and a 2-ethyl-3-methyl-cyclopropylgroup.

Specific examples of the alkenyl group that may be used for R⁵ includean ethenyl group, a 1-propenyl group, a 2-propenyl group, a1-methyl-1-ethenyl group, a 1-butenyl group, a 2-butenyl group, a3-butenyl group, a 2-methyl-1-propenyl group, a 2-methyl-2-propenylgroup, a 1-ethyl-ethenyl group, a 1-methyl-1-propenyl group, a1-methyl-2-propenyl group, a 1-pentenyl group, a 2-pentenyl group, a3-pentenyl group, a 4-pentenyl group, a 1-n-propyl-ethenyl group, a1-methyl-1-butenyl group, a 1-methyl-2-butenyl group, a1-methyl-3-butenyl group, a 2-ethyl-2-propenyl group, a2-methyl-1-butenyl group, a 2-methyl-2-butenyl group, a2-methyl-3-butenyl group, a 3-methyl-1-butenyl group, a3-methyl-2-butenyl group, a 3-methyl-3-butenyl group, a1,1-dimethyl-2-propenyl group, a 1-isopropyl-ethenyl group, a1,2-dimethyl-1-propenyl group, a 1,2-dimethyl-2-propenyl group, a1-cyclopentenyl group, a 2-cyclopentenyl group, a 3-cyclopentenyl group,a 1-hexenyl group, a 2-hexenyl group, a 3-hexenyl group, a 4-hexenylgroup, a 5-hexenyl group, a 1-methyl-1-pentenyl group, a1-methyl-2-pentenyl group, a 1-methyl-3-pentenyl group, a1-methyl-4-pentenyl group, a 1-n-butyl-etenyl group, a2-methyl-1-pentenyl group, a 2-methyl-2-pentenyl group, a2-methyl-3-pentenyl group, a 2-methyl-4-pentenyl group, a2-n-propyl-2-propenyl group, a 3-methyl-1-pentenyl group, a3-methyl-2-pentenyl group, a 3-methyl-3-pentenyl group, a3-methyl-4-pentenyl group, a 3-ethyl-3-butenyl group, a4-methyl-1-pentenyl group, a 4-methyl-2-pentenyl group, a4-methyl-3-pentenyl group, a 4-methyl-4-pentenyl group, a1,1-dimethyl-2-butenyl group, a 1,1-dimethyl-3-butenyl group, a1,2-dimethyl-1-butenyl group, a 1,2-dimethyl-2-butenyl group, a1,2-dimethyl-3-butenyl group, a 1-methyl-2-ethyl-2-propenyl group, a1-s-butyl-etenyl group, a 1,3-dimethyl-1-butenyl group, a1,3-dimethyl-2-butenyl group, a 1,3-dimethyl-3-butenyl group, a1-isobutyl-etenyl group, a 2,2-dimethyl-3-butenyl group, a2,3-dimethyl-1-butenyl group, a 2,3-dimethyl-2-butenyl group, a2,3-dimethyl-3-butenyl group, a 2-isopropyl-2-propenyl group, a3,3-dimethyl-1-butenyl group, a 1-ethyl-1-butenyl group, a1-ethyl-2-butenyl group, a 1-ethyl-3-butenyl group, a1-n-propyl-1-propenyl group, a 1-n-propyl-2-propenyl group, a2-ethyl-1-butenyl group, a 2-ethyl-2-butenyl group, a 2-ethyl-3-butenylgroup, a 1,1,2-trimethyl-2-propenyl group, a 1-tert-butyl-etenyl group,a 1-methyl-1-ethyl-2-propenyl group, a 1-ethyl-2-methyl-1-propenylgroup, a 1-ethyl-2-methyl-2-propenyl group, a 1-isopropyl-1-propenylgroup, a 1-isopropyl-2-propenyl group, a 1-methyl-2-cyclopentenyl group,a 1-methyl-3-cyclopentenyl group, a 2-methyl-1-cyclopentenyl group, a2-methyl-2-cyclopentenyl group, a 2-methyl-3-cyclopentenyl group, a2-methyl-4-cyclopentenyl group, a 2*methyl-5-cyclopentenyl group, a2-methylene-cyclopentyl group, a 3-methyl-1-cyclopentenyl group, a3-methyl-2-cyclopentenyl group, a 3-methyl-3-cyclopentenyl group, a3-methyl-4-cyclopentenyl group, a 3-methyl-5-cyclopentenyl group, a3-methylene-cyclopentyl group, a 1-cyclohexenyl group, a 2-cyclohexenylgroup and a 3-cyclohexenyl group.

Specific examples of the alkynyl group that may be used for R⁵ includean ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynylgroup, a 2-butynyl group, a 3-butynyl group, a 1-methyl-2-propynylgroup, a 1-pentynyl group, a 2-pentynyl group, a 3-pentynyl group, a4-pentynyl group, a 1-methyl-2-butynyl group, a 1-methyl-3-butynylgroup, a 2-methyl-3-butynyl group, a 3-methyl-1-butynyl group, a1,1-dimethyl-2-propynyl group, a 2-ethyl-2-propynyl group, a 1-hexynyl,a 2-hexynyl group, a 3-hexynyl group, a 4-hexynyl group, a 5-hexynylgroup, a 1-methyl-2-pentynyl group, a 1-methyl-3-pentynyl group, a1-methyl-4-pentynyl group, a 2-methyl-3-pentynyl group, a2-methyl-4-pentynyl group, a 3-methyl-1-pentynyl group, a3-methyl-4-pentynyl group, a 4-methyl-1-pentynyl group, a4-methyl-2-pentynyl group, a 1,1-dimethyl-2-butynyl group, a1,1-dimethyl-3-butynyl group, a 1,2-dimethyl-3-butynyl group, a2,2-dimethyl-3-butynyl group, a 3,3-dimethyl-1-butynyl group, a1-ethyl-2-butynyl group, a 1-ethyl-3-butynyl group, a1-n-propyl-2-propynyl group, a 2-ethyl-3-butynyl group, a1-methyl-1-ethyl-2-propynyl group and a 1-isopropyl-2-propynyl group.

Specific examples of the alkylcarbonyl group that may be used for R⁵include a methylcarbonyl group, an ethylcarbonyl group, ann-propylcarbonyl group, an isopropylcarbonyl group, acyclopropylcarbonyl group, an n-butylcarbonyl group, an isobutylcarbonylgroup, an s-butylcarbonyl group, a tert-butylcarbonyl group, acyclobutylcarbonyl group, a 1-methyl-cyclopropylcarbonyl group, a2-methyl-cyclopropylcarbonyl group, an n-pentylcarbonyl group, a1-methyl-n-butylcarbonyl group, a 2-methyl-n-butylcarbonyl group, a3-methyl-n-butylcarbonyl group, a 1,1-dimethyl-n-propylcarbonyl group, a1,2-dimethyl-n-propylcarbonyl group, a 2,2-dimethyl-n-propylcarbonylgroup, a 1-ethyl-n-propylcarbonyl group, a cyclopentylcarbonyl group, a1-methyl-cyclobutylcarbonyl group, a 2-methyl-cyclobutylcarbonyl group,a 3-methyl-cyclobutylcarbonyl group, a 1,2-dimethyl-cyclopropylcarbonylgroup, a 2,3-dimethyl-cyclopropylcarbonyl group, a1-ethyl-cyclopropylcarbonyl group, a 2-ethyl-cyclopropylcarbonyl group,an n-hexylcarbonyl group, a 1-methyl-n-pentylcarbonyl group, a2-methyl-n-pentylcarbonyl group, a 3-methyl-n-pentylcarbonyl group, a4-methyl-n-pentylcarbonyl group, a 1,1-dimethyl-n-butylcarbonyl group, a1,2-dimethyl-n-butylcarbonyl group, a 1,3-dimethyl-n-butylcarbonylgroup, a 2,2-dimethyl-n-butylcarbonyl group, a2,3-dimethyl-n-butylcarbonyl group, a 3,3-dimethyl-n-butylcarbonylgroup, a 1-ethyl-n-butyl carbonyl group, a 2-ethyl-n-butylcarbonylgroup, a 1,1,2-trimethyl-n-propylcarbonyl group, a1,2,2-trimethyl-n-propylcarbonyl group, a1-ethyl-1-methyl-n-propylcarbonyl group, a1-ethyl-2-methyl-n-propylcarbonyl group, a cyclohexylcarbonyl group, a1-methyl-cyclopentylcarbonyl group, a 2-methyl-cyclopentylcarbonylgroup, a 3-methyl-cyclopentylcarbonyl group, a1-ethyl-cyclobutylcarbonyl group, a 2-ethyl-cyclobutylcarbonyl group, a3-ethyl-cyclobutylcarbonyl group, a 1,2-dimethyl-cyclobutylcarbonylgroup, a 1,3-dimethyl-cyclobutylcarbonyl group, a2,2-dimethyl-cyclobutylcarbonyl group, a 2,3-dimethyl-cyclobutylcarbonylgroup, a 2,4-dimethyl-cyclobutylcarbonyl group, a3,3-dimethyl-cyclobutylcarbonyl group, a 1-n-propyl-cyclopropylcarbonylgroup, a 2-n-propyl-cyclopropylcarbonyl group, a1-isopropyl-cyclopropylcarbonyl group, a 2-isopropyl-cyclopropylcarbonylgroup, a 1,2,2-trimethyl-cyclopropylcarbonyl group, a1,2,3-trimethyl-cyclopropylcarbonyl group, a2,2,3-trimethyl-cyclopropylcarbonyl group, a1-ethyl-2-methyl-cyclopropylcarbonyl group, a2-ethyl-1-methyl-cyclopropylcarbonyl group, a2-ethyl-2-methyl-cyclopropylcarbonyl group and a2-ethyl-3-methyl-cyclopropylcarbonyl group.

Specific examples of the alkylcarbonylamino group that may be used forR⁵ a methylcarbonylamino group, an ethylcarbonylamino group, ann-propylcarbonylamino group, an isopropylcarbonylamino group, acyclopropylcarbonylamino group, an n-butylcarbonylamino group, anisobutylcarbonylamino group, an s-butylcarbonylamino group, atert-butylcarbonylamino group, a cyclobutylcarbonylamino group, a1-methyl-cyclopropylcarbonylamino group, a2-methyl-cyclopropylcarbonylamino group, an n-pentylcarbonylamino group,a 1-methyl-n-butylcarbonylamino group, a 2-methyl-n-butylcarbonylaminogroup, a 3-methyl-n-butylcarbonylamino group, a1,1-dimethyl-n-propylcarbonylamino group, a1,2-dimethyl-n-propylcarbonylamino group, a2,2-dimethyl-n-propylcarbonylamino group, a1-ethyl-n-propylcarbonylamino group, a cyclopentylcarbonylamino group, a1-methyl-cyclobutylcarbonylamino group, a2-methyl-cyclobutylcarbonylamino group, a3-methyl-cyclobutylcarbonylamino group, a1,2-dimethyl-cyclopropylcarbonylamino group, a2,3-dimethyl-cyclopropylcarbonylamino group, a1-ethyl-cyclopropylcarbonylamino group, a2-ethyl-cyclopropylcarbonylamino group, an n-hexylcarbonylamino group, a1-methyl-n-pentylcarbonylamino group, a 2-methyl-n-pentylcarbonylaminogroup, a 3-methyl-n-pentylcarbonylamino group, a4-methyl-n-pentylcarbonylamino group, a1,1-dimethyl-n-butylcarbonylamino group, a1,2-dimethyl-n-butylcarbonylamino group, a1,3-dimethyl-n-butylcarbonylamino group, a2,2-dimethyl-n-butylcarbonylamino group, a2,3-dimethyl-n-butylcarbonylamino group, a3,3-dimethyl-n-butylcarbonylamino group, a 1-ethyl-n-butylcarbonylaminogroup, a 2-ethyl-n-butylcarbonylamino group, a1,1,2-trimethyl-n-propylcarbonylamino group, a1,2,2-trimethyl-n-propylcarbonylamino group, a1-ethyl-1-methyl-n-propylcarbonylamino group, a1-ethyl-2-methyl-n-propylcarbonylamino group, a cyclohexylcarbonylaminogroup, a 1-methyl-cyclopentylcarbonylamino group, a2-methyl-cyclopentylcarbonylamino group, a3-methyl-cyclopentylcarbonylamino group, a1-ethyl-cyclobutylcarbonylamino group, a 2-ethyl-cyclobutylcarbonylaminogroup, a 3-ethyl-cyclobutylcarbonylamino group, a1,2-dimethyl-cyclobutylcarbonylamino group, a1,3-dimethyl-cyclobutylcarbonylamino group, a2,2-dimethyl-cyclobutylcarbonylamino group, a2,3-dimethyl-cyclobutylcarbonylamino group, a2,4-dimethyl-cyclobutylcarbonylamino group, a3,3-dimethyl-cyclobutylcarbonylamino group, a1-n-propyl-cyclopropylcarbonylamino group, a2-n-propyl-cyclopropylcarbonylamino group, a1-isopropyl-cyclopropylcarbonylamino group, a2-isopropyl-cyclopropylcarbonylamino group, a1,2,2-trimethyl-cyclopropylcarbonylamino group, a1,2,3-trimethyl-cyclopropylcarbonylamino group, a2,2,3-trimethyl-cyclopropylcarbonylamino group, a1-ethyl-2-methyl-cyclopropylcarbonylamino group, a2-ethyl-1-methyl-cyclopropylcarbonylamino group, a2-ethyl-2-methyl-cyclopropylcarbonylamino group and a2-ethyl-3-methyl-cyclopropylcarbonylamino group.

Specific examples of the alkyloxyalkyl group that may be used for R⁵include a methyloxymethyl group, an ethyloxyethyl group, anethyloxymethyl group, a propyloxypropyl group, a propyloxymethyl group,and a tert-butyloxy-tert-butyl group.

Specific examples of the alkylamino groups that may be used for R⁵include a methylamino group, an ethylamino group, an n-propylaminogroup, an isopropylamino group, a cyclopropylamino group, ann-butylamino group, an isobutylamino group, an s-butylamino group, atert-butylamino group, a cyclobutylamino group, a1-methyl-cyclopropylamino group, a 2-methyl-cyclopropylamino group, ann-pentylamino group, a 1-methyl-n-butylamino group, a2-methyl-n-butylamino group, a 3-methyl-n-butylamino group and a1,1-dimethyl-n-propylamino group.

Specific examples of the alkyldiamino groups that may be used for R⁵include a methyldiamino group, an ethyldiamino group, an n-propyldiaminogroup, an isopropyldiamino group, a cyclopropyldiamino group, ann-butyldiamino group, an isobutyldiamino group, an s-butyldiamino group,a tert-butyldiamino group, a cyclobutyldiamino group, a1-methyl-cyclopropyldiamino group, a 2-methyl-cyclopropyldiamino group,an n-pentyldiamino group, a 1-methyl-n-butyldiamino group, a2-methyl-n-butyldiamino group, a 3-methyl-n-butyldiamino group and a1,1-dimethyl-n-propyldiamino group.

In an embodiment in which the floating cross-linking agent is apolyglycidil ether, the floating cross-linking agent has the followingstructure:

where m² represented an integer of 2 to 6 and R⁶ represents (similar tothe groups described above with respect to the polyether polyol) analkyl group having 1 to 10 carbon atom(s), an alkenyl group having 2 to6 carbon atoms, an alkynyl group having 2 to 10 carbon atoms,alkylcarbonyl group having 2 to 10 carbon atoms, an alkylcarbonylaminogroup having 2 to 10 carbon atoms, an alkyloxyalkyl group having 2 to 10carbon atoms, an alkylamino group having 1 to 10 carbon atom(s), analkyldiamino group having 1 to 10 carbon atom(s) or a combinationthereof; has either a straight, branched, or cyclic structure; and is anorganic group capable of having a valence number of 2 to 6 according tothe number m² of glycidyl ether groups.

In an embodiment in which the floating cross-linking agent is a vinylether, the floating cross-linking agent has the following structure:R⁷—(X¹—O—CH═CH₂)_(n2)where n² is from one to six; R⁷ is an aryl group or an alkyl group; andX¹ is an alkyl, alkoxys, carboxys, or combinations thereof.

In particular embodiments in which the floating cross-linking agent is avinyl ether, the floating cross-linking agent has one of the followingstructures:

In an embodiment in which the floating cross-linking agent is aglycouril, the floating cross-linking agent may be a methylatedglycouril such as a methoxy methylated glycouril. In a particularembodiment in which the floating cross-linking agent is a methoxymethylated glycouril the floating cross-linking agent has the followingstructure:

In an embodiment in which the floating cross-linker is a triazene, thefloating cross-linker may be such triazenes as3,3-dimethyl-1-phenylenetriaze, an aryl group containing3,3-dimethyl-1-phylenetriazene, or bis(triazene). In a particularembodiment, the floating cross-linking agent that is a triazene with thefollowing structure:

In an embodiment the floating cross-linking agent also comprises asubstituted fluorine atom that has been incorporated into the structureof the floating cross-linking agent. In a particular embodiment thefluorine atom may be incorporated into the cross-linking structure asone or more fluorine atoms substituted for, e.g., a hydrogen atom withinan alkyl group located within the structure of the floatingcross-linking agent.

Alternatively, the fluorine atom may be part of an alkyl fluoride groupthat is substituted into the structure of the floating cross-linkingagent. As particular examples, the fluorine atom may be incorporatedinto an alkyl fluoride group that has one of the following structures:

However, any suitable number of carbon and fluorine atoms mayalternatively be utilized.

Additionally, as one of ordinary skill in the art will recognize, theprecise examples listed above regarding the structures and groups thatmay be used within the floating cross-linking agent are merely intendedto be illustrative and are not intended to list every possible structureor groups that may be utilized to form the floating cross-linking agent.Any suitable alternative structures and any suitable alternative groupsmay be used to form the floating cross-linking agent, and all suchstructures and groups are fully intended to be included within the scopeof the embodiments.

The individual components of the BARC layer 105 may be placed into theBARC solvent in order to aid in the mixing and placement of the BARClayer 105. To aid in the mixing and placement of the BARC layer 105, thesolvent is chosen at least in part based upon the materials and monomerschosen for the polymer resin of the BARC layer 105 as well as thecatalyst. In particular, the BARC solvent is chosen such that thepolymer resin, the catalysts, and the floating cross-linking agent canbe evenly dissolved into the BARC solvent and dispensed upon thesubstrate 101 and the fins 103.

In an embodiment the BARC solvent may be an organic solvent, and maycomprise any suitable solvent such as ketones, alcohols, polyalcohols,ethers, glycol ethers, cyclic ethers, aromatic hydrocarbons, esters,propionates, lactates, lactic esters, alkylene glycol monoalkyl ethers,alkyl lactates, alkyl alkoxypropionates, cyclic lactones, monoketonecompounds that contain a ring, alkylene carbonates, alkyl alkoxyacetate,alkyl pyruvates, ethylene glycol alkyl ether acetates, diethyleneglycols, propylene glycol alkyl ether acetates, alkylene glycol alkylether esters, alkylene glycol monoalkyl esters, or the like.

Specific examples of materials that may be used as the BARC solventinclude, acetone, methanol, ethanol, toluene, xylene,4-hydroxy-4-methyl-2-pentatone, tetrahydrofuran, methyl ethyl ketone,cyclohexanone, methyl isoamyl ketone, 2-heptanone, ethylene glycol,ethylene glycol monoacetate, ethylene glycol dimethyl ether, ethyleneglycol methylethyl ether, ethylene glycol monoethyl ether, methylcellosolve acetate, ethyl cellosolve acetate, diethylene glycol,diethylene glycol monoacetate, diethylene glycol monomethyl ether,diethylene glycol diethyl ether, diethylene glycol dimethyl ether,diethylene glycol ethylmethyl ether, diethylene glycol monoethyl ether,diethylene glycol monobutyl ether, ethyl 2-hydroxypropionate, methyl2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, ethylethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-2-methylbutanate,methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl acetate, butylacetate, methyl lactate and ethyl lactate, propylene glycol, propyleneglycol monoacetate, propylene glycol monoethyl ether acetate, propyleneglycol monomethyl ether acetate, propylene glycol monopropyl methylether acetate, propylene glycol monobutyl ether acetate, propyleneglycol monobutyl ether acetate, propylene glycol monomethyl etherpropionate, propylene glycol monoethyl ether propionate, propyleneglycol methyl ether adcetate, proplylene glycol ethyl ether acetate,ethylene glycol monomethyl ether acetate, ethylene glycol monoethylether acetate, propylene glycol monomethyl ether, propylene glycolmonoethyl ether, propylene glycol monopropyl ether, propylene glycolmonobutyl ether, ethylene glycol monomethyl ether, ethylene glycolmonoethyl ether, propyl lactate, and butyl lactate, ethyl3-ethoxypropionate, methyl 3-methoxypropionate, methyl3-ethoxypropionate, and ethyl 3-methoxypropionate, β-propiolactone,β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone,β-methyl-γ-butyrolactone, γ-valerolactone, γ-caprolactone, γ-octanoiclactone, α-hydroxy-γ-butyrolactone, 2-butanone, 3-methylbutanone,pinacolone, 2-pentanone, 3-pentanone, 4-methyl-2-pentanone,2-methyl-3-pentanone, 4,4-dimethyl-2-pentanone,2,4-dimethyl-3-pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2-hexanone,3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone,2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4-heptanone,2-octanone, 3-octanone, 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone,3-decanone, 4-decanone, 5-hexene-2-one, 3-pentene-2-one, cyclopentanone,2-methylcyclopentanone, 3-methylcyclopentanone,2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopentanone,cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone,4-ethylcyclohexanone, 2,2-dimethylcyclohexanone,2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone,2-methylcycloheptanone, 3-methylcycloheptanone, pylene carbonate,vinylene carbonate, ethylene carbonate, and butylene carbonate,acetate-2-methoxyethyl, acetate-2-ethoxyethyl,acetate-2-(2-ethoxyethoxy)ethyl, acetate-3-methoxy-3-methylbutyl,acetate-1-methoxy-2-propyl, dipropylene glycol, monomethylether,monoethylether, monopropylether, monobutylehter, monophenylether,dipropylene glycol monoacetate, dioxane, etheyl lactate, methyl acetate,ethyl acetate, butyl acetate, methyl puruvate, ethyl puruvate, propylpyruvate, methyl methoxypropionate, ethyl ethoxypropionate,n-methylpyrrolidone (NMP), 2-methoxyethyl ether (diglyme), ethyleneglycol monom-ethyl ether, propylene glycol monomethyl ether; methylproponiate, ethyl proponiate and ethyl ethoxy proponiate, methylethylketone, cyclohexanone, 2-heptanone, carbon dioxide, cyclopentatone,cyclohexanone, ethyl 3-ethocypropionate, propylene glycol methyl etheracetate (PGMEA), methylene cellosolve, butyle acetate, and2-ethoxyethanol, N-methylformamide, N,N-dimethylformamide,N-methylformanilide, N-methylacetamide, N,N-dimethylacetamide,N-methylpyrrolidone, dimethylsulfoxide, benzyl ethyl ether, dihexylether, acetonylacetone, isophorone, caproic acid, caprylic acid,1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate,diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate,propylene carbonate, phenyl cellosolve acetate, or the like.

However, as one of ordinary skill in the art will recognize, thematerials listed and described above as examples of materials that maybe utilized for the solvent component of the BARC layer 105 are merelyillustrative and are not intended to limit the embodiments. Rather, anysuitable material that may dissolve the polymer resin, the catalyst, andthe floating cross-linking layer may alternatively be utilized to helpmix and apply the BARC layer 105. All such materials are fully intendedto be included within the scope of the embodiments.

Additionally, other components may also be added into the material forthe BARC layer 105 if desired. For example, in an embodiment themonomeric dyes, surface leveling agents, adhesion promoters,anti-foaming agent, and the like, may alternatively be utilized. Anysuitable additive may be added into the material for the BARC layer 105,and all such additives are fully intended to be included within thescope of the embodiments.

In an embodiment the polymer resin, the catalysts, and the floatingcross-linking agent, along with any desired additives or other agents,are added to the BARC solvent to form the material for the BARC layer105. Once added, the mixture is then mixed in order to achieve an evenand constant composition throughout the material for the BARC layer 105in order to ensure that there are no defects caused by an uneven mixingor non-constant composition of the material for the BARC layer 105. Oncemixed together, the material for the BARC layer 105 may either be storedprior to its usage or else used immediately.

In its original mixed form, the material for the BARC layer 105 maycomprise a constant composition of components, with the polymer resinhaving a concentration of between about 0.1% and about 60%, the catalysthaving a concentration of between about 0.01% and about 10%, and thefloating cross-linking agent having a concentration of between about0.01% and about 30%. However, while these concentrations areillustrative, any suitable combinations of the various components of thematerial for the BARC layer 105 may be used, and all such combinationsare fully intended to be included within the scope of the embodiments.

Once the material for the BARC layer 105 has been prepared, the materialfor the BARC layer 105 may be utilized by initially applying thematerial for the BARC layer 105 onto the substrate 101 and the fins 103.The material for the BARC layer 105 may be applied to the substrate 101and the fins 103 so that the material for the BARC layer 105 coats anupper exposed surface of the substrate 101 and the fins 103, and may beapplied using a process such as a spin-on coating process, a dip coatingmethod, an air-knife coating method, a curtain coating method, awire-bar coating method, a gravure coating method, a lamination method,an extrusion coating method, combinations of these, or the like. In anembodiment the material for the BARC layer 105 may be initially appliedsuch that it has a constant concentration and has a thickness over a topof the fins 103 of between about 10 nm and about 1000 nm, such as about100 nm.

FIG. 2 illustrates the floating cross-linker forming a floating region201 along a top surface of the BARC layer 105. In an embodiment thefloating cross-linker will move to the top of the BARC layer 105 as theBARC layer 105 is being applied, e.g., in the spin-on process. Thismovement is initiated because the addition of the fluorine atom causesthe floating cross-linker to have a high surface energy. This highsurface energy, coupled with the low interaction between the fluorineatoms and the other atoms within the BARC layer 105, will initiate themovement of the floating cross-linker to the top surface of the BARClayer 105.

In an embodiment with the formation of the floating region 201, thefloating region 201 will have a higher concentration of the floatingcross-linker than a remainder of the BARC layer 105, such as by having aconcentration of between about 0.01% and about 10%, such as about 2%,while the remainder of the BARC layer 105 (outside of the floatingregion 201) will have a concentration of the floating cross-linker nogreater than about 5%. Additionally, the floating region 201 will have athickness T₁ of between about 10 Å and about 1000 Å, such as about 100Å. However, these dimensions and concentrations may vary and areintended to be illustrative only, and any benefits may be derived fromsuitable concentrations different from those listed herein.

FIG. 3 illustrates a pre-bake of the BARC layer 105 (represented in FIG.3 by the wavy lines labeled 301), including both the bake itself and itsresulting consequences. In an embodiment once the BARC layer 105 hasbeen applied to the substrate 101 and the fins 103, the pre-bake 301 ofthe BARC layer 105 is performed in order to cure and dry the BARC layer105 prior to an application of the photoresist 401. The curing anddrying of the BARC layer 105 removes a portion of the BARC solventcomponents but leaves behind the polymer resin, the catalysts, thecross-linking agent, and other additives. In an embodiment the pre-bake301 may be performed at a temperature suitable to evaporate the BARCsolvent, such as between about 40° C. and 150° C., although the precisetemperature depends upon the materials chosen for the BARC layer 105.The pre-bake 301 is performed for a time sufficient to cure and dry theBARC layer 105, such as between about 10 seconds to about 5 minutes,such as about 90 seconds. Additionally, the pre-bake will cause thefloating cross-linking agent to react with the polymer resin and beginbonding and cross-linking the individual polymers of the polymer resininto larger molecule polymers.

When all of the components of the material of the BARC layer 105 have aconstant concentration throughout the BARC layer 105, series issues infilling the gap between the fins 103 can occur during the pre-bake 301in which solvent evaporates and cross-linking occurs. In particular,because the solvent evaporates at the surface of the BARC layer 105, theconcentrations of the remaining components will increase, driving thecross-linking reaction to occur faster than within the remainder of theBARC layer 105, such as between the fins 103. As such, voids within theBARC layer 105 may be formed from this uneven reaction between the topof the BARC layer 105 and the remainder of the BARC layer 105.

In addition, the cross-linking reaction itself may cause voids to form.In particular, the cross-linking reaction will produce a number ofreaction by-products while the polymers of the polymer resin are bondingto each other. These reaction by-products may vaporize and outgas duringthe pre-bake 301, causing voids to occur between cross-linked polymersthroughout the BARC layer 105.

The cross-linking of the polymers, once mature, will also causeshrinkage to occur. In particular, as the polymers cross-link with eachother, the cross-linking density of the BARC layer 105 will go up,resulting in a lower overall volume for the BARC layer 105. This lowervolume will generate stresses along the surfaces to which the BARC layer105 is coated (e.g., the substrate 101 and the fins 103). These stressescan pull the BARC layer 105 away from surface structures and causingvoids to form adjacent to the surfaces such as the fins 103.

Additionally, the cross-linking reaction will also change the polymerresins to be more hydrophobic. This change will reduce the adhesionbetween the BARC layer 105 and the substrate 101. Such a reduction isadhesion, if a large enough reduction, can cause delamination andpeeling to occur between the BARC layer 105 and the substrate 101, whichcan detrimentally affect the performance of the BARC layer 105 duringfurther processing.

Finally, the while all of the above is occurring to form voids andpeeling within the BARC layer 105, the combination of the cross-linkingreaction and the removal of the solvent will also serve to harden andsolidify the materials within the BARC layer 105. This hardening willprevent the materials from flowing into the voids or the peeling,preventing the materials of the BARC layer 105 from correcting the voidsand peeling.

However, with the inclusion of the floating cross-linking agent and theformation of the floating region 201, the floating cross-linking agentwill be located along the top surface of the BARC layer 105. As such,the cross-linking reaction will occur primarily within the floatingregion 201 with the remainder of the BARC layer 105 that is not locatedwithin the floating region 201 having fewer cross-linking reactions and,thus, fewer polymers cross-linking.

Given this, the cross-linking reaction will occur primarily across thetop surface of the BARC layer 105, thereby providing the desiredprotection against the photoresist 401 which will be subsequentlyapplied as well as providing the desired anti-reflective properties.However, the cross-linking reaction elsewhere within the BARC layer 105will be reduced, leading to a reduction in all of the subsequentproblems caused by excessive cross-linking. In particular, there will beno significant film shrinkage outside of the floating region 201 andthere will be no significant cross-linking reaction by-products tooutgas outside of the floating region 201, thereby avoiding theformation of voids. Additionally, by avoiding the cross-linking reactionalong the interface of the BARC layer 105 and the substrate 101, thehydrophilicity of the BARC layer 105 will remain unchanged, leaving theadhesion the same and avoiding or reducing adhesion problems between theBARC layer 105 and the substrate 101. Finally, as the remainder of theBARC layer 105 has fewer cross-linked polymers, the BARC layer 105 maystill be able to flow during the course of the cross-linking reactions,thereby filling some voids that may have formed at an early stage of thecross-linking reaction before the pre-bake 301 has been completed.

However, using the floating cross-linking agent is not the only methodor material that may be used to form the floating region 201. Rather,any suitable material that is involved within the cross-linking reactionand which may be induced to float to the top surface of the BARC layer105 and form the floating region 201 may alternatively be used. All suchmaterials and methods are fully intended to be included within the scopeof the embodiments.

For example, instead of using a floating cross-linking agent, in onealternative embodiment a floating polymer resin may be utilized insteadof the floating cross-linking agent. In this embodiment the floatingpolymer resin may comprise a polymer resin as described above withrespect to FIG. 1, but in which a fluorine atom has been substitutedinto the structure. For example, in an embodiment in which the floatingpolymer resin comprises an alkyl group, the fluorine atom may besubstituted for a hydrogen atom within one or more of the alkyl groupsof the polymer.

In another embodiment the fluorine atom may be part of a fluoralkylgroup that is substituted into the polymer of the polymer resin. As aparticular example, the fluorine atom may be incorporated into afluoroalkyl groups such as the fluoroalkyl groups discussed above withrespect to the floating cross-linking agent (e.g., CF₃, C₂F₅, C₃F₇,etc.). In an embodiment in which the polymer resin comprises an alkylgroup, the fluoralkyl group may be substituted into the polymer resin toform the floating polymer resin by replacing one of the alkyl groupswith the fluoroalkyl group to form the floating polymer resin.

In this embodiment, instead of the floating cross-linking agentdescribed above with respect to FIG. 1, the cross-linking agent may besimilar to the cross-linking agent described above for the floatingcross-linking agent (without the addition of the fluorine atom).Alternatively, the cross-linking agent may be a melamine based agent, aurea based agent, ethylene urea based agent, propylene urea based agent,glycoluril based agent, an aliphatic cyclic hydrocarbon having ahydroxyl group, a hydroxyalkyl group, or a combination of these, oxygencontaining derivatives of the aliphatic cyclic hydrocarbon, glycolurilcompounds, etherified amino resins, combinations of these, or the like.

Specific examples of materials that may be utilized as a cross-linkingagent include melamine, acetoguanamine, benzoguanamine, urea, ethyleneurea, or glycoluril with formaldehyde, glycoluril with a combination offormaldehyde and a lower alcohol, hexamethoxymethylmelamine,bismethoxymethylurea, bismethoxymethylbismethoxyethylene urea,tetramethoxymethylglycoluril, and tetrabutoxymethylglycoluril, mono-,di-, tri-, or tetra-hydroxymethylated glycoluril, mono-, di-, tri-,and/or tetra-methoxymethylated glycoluril, mono-, di-, tri-, and/ortetra-ethoxymethylated glycoluril, mono-, di-, tri-, and/ortetra-propoxymethylated glycoluril, and mono-, di-, tri-, and/ortetra-butoxymethylated glycoluril,2,3-dihydroxy-5-hydroxymethylnorbornane,2-hydroy-5,6-bis(hydroxymethyl)norbornane, cyclohexanedimethanol,3,4,8(or 9)-trihydroxytricyclodecane, 2-methyl-2-adamantanol,1,4-dioxane-2,3-diol and 1,3,5-trihydroxycyclohexane, tetramethoxymethylglycoluril, methylpropyltetramethoxymethyl glycoluril, andmethylphenyltetramethoxymethylglycoluril,2,6-bis(hydroxymethyl)p-cresol, N-methoxymethyl- orN-butoxymethyl-melamine. Additionally, compounds obtained by reactingformaldehyde, or formaldehyde and lower alcohols with aminogroup-containing compounds, such as melamine, acetoguanamine,benzoguanamine, urea, ethylene urea and glycoluril, and substituting thehydrogen atoms of the amino group with hydroxymethyl group or loweralkoxymethyl group, examples being hexamethoxymethylmelamine,bismethoxymethyl urea, bismethoxymethylbismethoxyethylene urea,tetramethoxymethyl glycoluril and tetrabutoxymethyl glycoluril,copolymers of 3-chloro-2-hydroxypropyl methacrylate and methacrylicacid, copolymers of 3-chloro-2-hydroxypropyl methacrylate and cyclohexylmethacrylate and methacrylic acid, copolymers of3-chloro-2-hydroxypropyl methacrylate and benzyl methacrylate andmethacrylic acid, bisphenol A-di(3-chloro-2-hydroxypropyl)ether,poly(3-chloro-2-hydroxypro-pyl)ether of a phenol novolak resin,pentaerythritol tetra(3-chloro-2-hydroxypropyl)ether, trimethylolmethanetri(3-chloro-2-hydroxypropyl)ether phenol, bisphenolA-di(3-acetoxy-2-hydroxypropyl)ether,poly(3-acetoxy-2-hydroxypropyl)ethe-r of a phenol novolak resin,pentaerythritol tetra(3-acetoxy-2-hydroxyprop-yl)ether, pentaerythritolpoly(3-chloroacetoxy-2-hydroxypropyl)ether, trimethylolmethanetri(3-acetoxy-2-hydroxypropyl)ether, combinations of these, or the like.

In this embodiment in which the floating polymer resin is utilizedinstead of the floating cross-linking agent, the floating polymer resinmay have an initial concentration within the material for the BARC layer105 of between about 0.1% and about 60%, while the cross-linking agentmay have an initial concentration of between about 0.01% and about 30%.The material for the BARC layer 105 may be dispersed as described abovewith respect to FIG. 1 (e.g., a spin-on process) so that the BARC layer105 initially has a constant concentration when it is dispersed.

However, similar to the embodiment described above with respect to FIG.2, once dispersed, the floating polymer resin, with the addition of thefluorine atom, will rise to the top of the BARC layer 105, forming thefloating region 201 (see FIG. 2), during the dispensing process. Withthe floating region 201 at the top of the BARC layer 105, the pre-bakeprocess will initiate the cross-linking reaction primarily in thefloating region 201 and any cross-linking reactions outside of thefloating region 201 will be reduced. By performing the cross-linkingreaction adjacent to the top surface of the BARC layer 105, defectscaused by voids and delimanation may be reduced or eliminated.

In yet another embodiment, instead of using the floating cross-linkingagent or the floating polymer, the floating region 201 may be formed byusing a floating catalyst. In this embodiment the floating catalyst maycomprise trifluoride catalyst as described above with respect to FIG. 1,but in which a fluorine atom has been substituted into the structure.For example, in an embodiment in which the floating catalyst comprisesan alkyl group, the fluorine atom may be substituted for a hydrogen atomwithin one or more of the alkyl groups of the catalyst.

In another embodiment the fluorine atom may be part of a fluoralkylgroup that is substituted into the catalyst. As a particular example,the fluorine atom may be incorporated into a fluoroalkyl groups such asthe fluoroalkyl groups discussed above with respect to the floatingcross-linking agent (e.g., CF₃, C₂F₅, C₃F₇, etc.). In an embodiment inwhich the catalyst comprises an alkyl group, the fluoralkyl group may besubstituted into the catalyst to form the floating catalyst by replacingone of the alkyl groups with the fluoroalkyl group to form the floatingcatalyst.

In specific embodiments, the fluorine atom or fluoroalkyl groups may besubstituted into catalysts such as the following:

In this embodiment in which the floating catalyst is utilized instead ofthe floating cross-linking agent or the floating polymer resin, thefloating catalyst may have an initial concentration within the materialfor the BARC layer 105 of between about 0.01% and about 10%. Thematerial for the BARC layer 105 may be dispersed as described above withrespect to FIG. 1 (e.g., a spin-on process) so that the material of theBARC layer 105 initially has a constant concentration when it isdispersed.

However, similar to the embodiment described above with respect to FIG.2, once dispersed, the floating catalyst, with the addition of thefluorine atom, will rise to the top of the BARC layer 105, forming thefloating region 201 (see FIG. 2), during the dispensing process. Withthe floating region 201 at the top of the BARC layer 105, the pre-bakeprocess will initiate the cross-linking reaction only in the floatingregion 201 and any cross-linking reactions outside of the floatingregion 201 will be reduced or eliminated, thereby eliminating orreducing voids or delaminating problems.

FIGS. 4A-4B illustrate an application, exposure, and development of aphotoresist 401 over the BARC layer 105. In an embodiment thephotoresist 401 includes a photoresist polymer resin along with one ormore photoactive compounds (PACs) in a photoresist solvent. In anembodiment the photoresist polymer resin may comprise a hydrocarbonstructure (such as a alicyclic hydrocarbon structure) that contains oneor more groups that will decompose (e.g., an acid labile group) orotherwise react when mixed with acids, bases, or free radicals generatedby the PACs (as further described below). In an embodiment thehydrocarbon structure comprises a repeating unit that forms a skeletalbackbone of the photoresist polymer resin. This repeating unit mayinclude acrylic esters, methacrylic esters, crotonic esters, vinylesters, maleic diesters, fumaric diesters, itaconic diesters,(meth)acrylonitrile, (meth)acrylamides, styrenes, vinyl ethers,combinations of these, or the like.

Specific structures which may be utilized for the repeating unit of thehydrocarbon structure include methyl acrylate, ethyl acrylate, n-propylacrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate,tert-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate,acetoxyethyl acrylate, phenyl acrylate, 2-hydroxyethyl acrylate,2-methoxyethyl acrylate, 2-ethoxyethyl acrylate,2-(2-methoxyethoxy)ethyl acrylate, cyclohexyl acrylate, benzyl acrylate,2-alkyl-2-adamantyl(meth)acrylate ordialkyl(1-adamantyl)methyl(meth)acrylate, methyl methacrylate, ethylmethacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butylmethacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-hexylmethacrylate, 2-ethylhexyl methacrylate, acetoxyethyl methacrylate,phenyl methacrylate, 2-hydroxyethyl methacrylate, 2-methoxyethylmethacrylate, 2-ethoxyethyl methacrylate, 2-(2-methoxyethoxy)ethylmethacrylate, cyclohexyl methacrylate, benzyl methacrylate,3-chloro-2-hydroxypropyl methacrylate, 3-acetoxy-2-hydroxypropylmethacrylate, 3-chloroacetoxy-2-hydroxypropyl methacrylate, butylcrotonate, hexyl crotonate and the like. Examples of the vinyl estersinclude vinyl acetate, vinyl propionate, vinyl butylate, vinylmethoxyacetate, vinyl benzoate, dimethyl maleate, diethyl maleate,dibutyl maleate, dimethyl fumarate, diethyl fumarate, dibutyl fumarate,dimethyl itaconate, diethyl itaconate, dibutyl itaconate, acrylamide,methyl acrylamide, ethyl acrylamide, propyl acrylamide, n-butylacrylamide, tert-butyl acrylamide, cyclohexyl acrylamide, 2-methoxyethylacrylamide, dimethyl acrylamide, diethyl acrylamide, phenyl acrylamide,benzyl acrylamide, methacrylamide, methyl methacrylamide, ethylmethacrylamide, propyl methacrylamide, n-butyl methacrylamide,tert-butyl methacrylamide, cyclohexyl methacrylamide, 2-methoxyethylmethacrylamide, dimethyl methacrylamide, diethyl methacrylamide, phenylmethacrylamide, benzyl methacrylamide, methyl vinyl ether, butyl vinylether, hexyl vinyl ether, methoxyethyl vinyl ether, dimethylaminoethylvinyl ether and the like. Examples of the styrenes include styrene,methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene,isopropyl styrene, butyl styrene, methoxy styrene, butoxy styrene,acetoxy styrene, chloro styrene, dichloro styrene, bromo styrene, vinylmethyl benzoate, α-methyl styrene, maleimide, vinylpyridine,vinylpyrrolidone, vinylcarbazole, combinations of these, or the like.

In an embodiment the repeating unit of the hydrocarbon structure mayalso have either a monocyclic or a polycyclic hydrocarbon structuresubstituted into it, or else the monocyclic or polycyclic hydrocarbonstructure may be the repeating unit, in order to form an alicyclichydrocarbon structure. Specific examples of monocyclic structures thatmay be used include bicycloalkane, tricycloalkane, tetracycloalkane,cyclopentane, cyclohexane, or the like. Specific examples of polycyclicstructures that may be used include adamantine, norbornane, isobornane,tricyclodecane, tetracycododecane, or the like.

The group which will decompose, otherwise known as a leaving group or,in an embodiment in which the PAC is an photoacid generator, an acidlabile group, is attached to the hydrocarbon structure so that it willreact with the acids/bases/free radicals generated by the PACs duringexposure. In an embodiment the group which will decompose may be acarboxylic acid group, a fluorinated alcohol group, a phenolic alcoholgroup, a sulfonic group, a sulfonamide group, a sulfonylimido group, an(alkylsulfonyl) (alkylcarbonyl)methylene group, an(alkylsulfonyl)(alkyl-carbonyl)imido group, abis(alkylcarbonyl)methylene group, a bis(alkylcarbonyl)imido group, abis(alkylsylfonyl)methylene group, a bis(alkylsulfonyl)imido group, atris(alkylcarbonyl methylene group, a tris(alkylsulfonyl)methylenegroup, combinations of these, or the like. Specific groups that may beutilized for the fluorinated alcohol group include fluorinatedhydroxyalkyl groups, such as a hexafluoroisopropanol group. Specificgroups that may be utilized for the carboxylic acid group includeacrylic acid groups, methacrylic acid groups, or the like.

In an embodiment the photoresist polymer resin may also comprise othergroups attached to the hydrocarbon structure that help to improve avariety of properties of the polymerizable resin. For example, inclusionof a lactone group to the hydrocarbon structure assists to reduce theamount of line edge roughness after the photoresist 401 has beendeveloped, thereby helping to reduce the number of defects that occurduring development. In an embodiment the lactone groups may includerings having five to seven members, although any suitable lactonestructure may alternatively be used for the lactone group.

The photoresist polymer resin may also comprise groups that can assistin increasing the adhesiveness of the photoresist 401 to underlyingstructures (e.g., the BARC layer 105). In an embodiment polar groups maybe used to help increase the adhesiveness, and polar groups that may beused in this embodiment include hydroxyl groups, cyano groups, or thelike, although any suitable polar group may alternatively be utilized.

Optionally, the photoresist polymer resin may further comprise one ormore alicyclic hydrocarbon structures that do not also contain a groupwhich will decompose. In an embodiment the hydrocarbon structure thatdoes not contain a group which will decompose may include structuressuch as 1-adamantyl(meth)acrylate, tricyclodecanyl(meth)acrylate,cyclohexayl(meth)acrylate, combinations of these, or the like.

Additionally, the photoresist 401 also comprises one or more PACs. ThePACs may be photoactive components such as photoacid generators,photobase generators, free-radical generators, or the like, and the PACsmay be positive-acting or negative-acting. In an embodiment in which thePACs are a photoacid generator, the PACs may comprise halogenatedtriazines, onium salts, diazonium salts, aromatic diazonium salts,phosphonium salts, sulfonium salts, iodonium salts, imide sulfonate,oxime sulfonate, diazodisulfone, disulfone, o-nitrobenzylsulfonate,sulfonated esters, halogenerated sulfonyloxy dicarboximides,diazodisulfones, α-cyanooxyamine-sulfonates, imidesulfonates,ketodiazosulfones, sulfonyldiazoesters, 1,2-di(arylsulfonyl)hydrazines,nitrobenzyl esters, and the s-triazine derivatives, suitablecombinations of these, and the like.

Specific examples of photoacid generators that may be used includeα.-(trifluoromethylsulfonyloxy)-bicyclo[2.2.1]hept-5-ene-2,3-dicarbo-ximide(MDT), N-hydroxy-naphthalimide (DDSN), benzoin tosylate,t-butylphenyl-α-(p-toluenesulfonyloxy)-acetate andt-butyl-α-(p-toluenesulfonyloxy)-acetate, triarylsulfonium anddiaryliodonium hexafluoroantimonates, hexafluoroarsenates,trifluoromethanesulfonates, iodonium perfluorooctanesulfonate,N-camphorsulfonyloxynaphthalimide,N-pentafluorophenylsulfonyloxynaphthalimide, ionic iodonium sulfonatessuch as diaryl iodonium (alkyl or aryl) sulfonate andbis-(di-t-butylphenyl)iodonium camphanylsulfonate,perfluoroalkanesulfonates such as perfluoropentanesulfonate,perfluorooctanesulfonate, perfluoromethanesulfonate, aryl (e.g., phenylor benzyl) triflates such as triphenylsulfonium triflate orbis-(t-butylphenyl)iodonium triflate; pyrogallol derivatives (e.g.,trimesylate of pyrogallol), trifluoromethanesulfonate esters ofhydroxyimides, α,α′-bis-sulfonyl-diazomethanes, sulfonate esters ofnitro-substituted benzyl alcohols, naphthoquinone-4-diazides, alkyldisulfones, and the like.

In an embodiment in which the PACs are a free-radical generator, thePACs may comprise n-phenylglycine, aromatic ketones such asbenzophenone, N,N′-tetramethyl-4,4′-diaminobenzophenone,N,N′-tetraethyl-4,4′-diaminobenzophenone,4-methoxy-4′-dimethylaminobenzo-phenone,3,3′-dimethyl-4-methoxybenzophenone,p,p′-bis(dimethylamino)benzo-phenone,p,p′-bis(diethylamino)-benzophenone, anthraquinone,2-ethylanthraquinone, naphthaquinone and phenanthraquinone, benzoinssuch as benzoin, benzoinmethylether, benzoinethylether,benzoinisopropylether, benzoin-n-butylether, benzoin-phenylether,methylbenzoin and ethybenzoin, benzyl derivatives such as dibenzyl,benzyldiphenyldisulfide and benzyldimethylketal, acridine derivativessuch as 9-phenylacridine and 1,7-bis(9-acridinyl)heptane, thioxanthonessuch as 2-chlorothioxanthone, 2-methylthioxanthone,2,4-diethylthioxanthone, 2,4-dimethylthioxanthone and2-isopropylthioxanthone, acetophenones such as 1,1-dichloroacetophenone,p-t-butyldichloro-acetophenone, 2,2-diethoxyacetophenone,2,2-dimethoxy-2-phenylacetophenone, and2,2-dichloro-4-phenoxyacetophenone, 2,4,5-triarylimidazole dimers suchas 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer,2-(o-chlorophenyl)-4,5-di-(m-methoxyphenyl imidazole dimer,2-(o-fluorophenyl)-4,5-diphenylimidazole dimer,2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer,2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer,2,4-di(p-methoxyphenyl)-5-phenylimidazole dimer,2-(2,4-dimethoxyphenyl)-4,5-diphenylimidazole dimer and2-(p-methylmercaptophenyl)-4,5-diphenylimidazole dimmer, suitablecombinations of these, or the like.

In an embodiment in which the PACs are a photobase generator, the PACsmay comprise quaternary ammonium dithiocarbamates, a aminoketones,oxime-urethane containing molecules such as dibenzophenoneoximehexamethylene diurethan, ammonium tetraorganylborate salts, andN-(2-nitrobenzyloxycarbonyl) cyclic amines, suitable combinations ofthese, or the like. However, as one of ordinary skill in the art willrecognize, the chemical compounds listed herein are merely intended asillustrated examples of the PACs and are not intended to limit theembodiments to only those PACs specifically described. Rather, anysuitable PAC may alternatively be utilized, and all such PACs are fullyintended to be included within the scope of the present embodiments.

The individual components of the photoresist 401 may be placed into aphotoresist solvent in order to aid in the mixing and placement of thephotoresist 401. To aid in the mixing and placement of the photoresist401, the photoresist solvent is chosen at least in part based upon thematerials chosen for the photoresist polymer resin as well as the PACs.In particular, the photoresist solvent is chosen such that thephotoresist polymer resin and the PACs can be evenly dissolved into thephotoresist solvent and dispensed upon the BARC layer 105.

In an embodiment the photoresist solvent may be an organic solvent, andmay comprise any suitable solvent such as ketones, alcohols,polyalcohols, ethers, glycol ethers, cyclic ethers, aromatichydrocarbons, esters, propionates, lactates, lactic esters, alkyleneglycol monoalkyl ethers, alkyl lactates, alkyl alkoxypropionates, cycliclactones, monoketone compounds that contain a ring, alkylene carbonates,alkyl alkoxyacetate, alkyl pyruvates, lactate esters, ethylene glycolalkyl ether acetates, diethylene glycols, propylene glycol alkyl etheracetates, alkylene glycol alkyl ether esters, alkylene glycol monoalkylesters, or the like.

Specific examples of materials that may be used as the photoresistsolvent for the photoresist 401 include, acetone, methanol, ethanol,toluene, xylene, 4-hydroxy-4-methyl-2-pentatone, tetrahydrofuran, methylethyl ketone, cyclohexanone, methyl isoamyl ketone, 2-heptanone,ethylene glycol, ethylene glycol monoacetate, ethylene glycol dimethylether, ethylene glycol methylethyl ether, ethylene glycol monoethylether, methyl cellosolve acetate, ethyl cellosolve acetate, diethyleneglycol, diethylene glycol monoacetate, diethylene glycol monomethylether, diethylene glycol diethyl ether, diethylene glycol dimethylether, diethylene glycol ethylmethyl ether, diethylene glycol monoethylether, diethylene glycol monobutyl ether, ethyl 2-hydroxypropionate,methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate,ethyl ethoxyacetate, ethyl hydroxyacetate, methyl2-hydroxy-2-methylbutanate, methyl 3-methoxypropionate, ethyl3-methoxypropionate, methyl 3-ethoxypropionate, ethyl3-ethoxypropionate, ethyl acetate, butyl acetate, methyl lactate andethyl lactate, propylene glycol, propylene glycol monoacetate, propyleneglycol monoethyl ether acetate, propylene glycol monomethyl etheracetate, propylene glycol monopropyl methyl ether acetate, propyleneglycol monobutyl ether acetate, propylene glycol monobutyl etheracetate, propylene glycol monomethyl ether propionate, propylene glycolmonoethyl ether propionate, propylene glycol methyl ether adcetate,proplylene glycol ethyl ether acetate, ethylene glycol monomethyl etheracetate, ethylene glycol monoethyl ether acetate, propylene glycolmonomethyl ether, propylene glycol monoethyl ether, propylene glycolmonopropyl ether, propylene glycol monobutyl ether, ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, propyl lactate, andbutyl lactate, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate,methyl 3-ethoxypropionate, and ethyl 3-methoxypropionate,β-propiolactone, β-butyrolactone, γ-butyrolactone,α-methyl-γ-butyrolactone, β-methyl-γ-butyrolactone, γ-valerolactone,γ-caprolactone, γ-octanoic lactone, α-hydroxy-γ-butyrolactone,2-butanone, 3-methylbutanone, pinacolone, 2-pentanone, 3-pentanone,4-methyl-2-pentanone, 2-methyl-3-pentanone, 4,4-dimethyl-2-pentanone,2,4-dimethyl-3-pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2-hexanone,3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone,2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4-heptanone,2-octanone, 3-octanone, 2-nonanone, 3-nonanone, 5-nonanone, 2-decanone,3-decanone, 4-decanone, 5-hexene-2-one, 3-pentene-2-one, cyclopentanone,2-methylcyclopentanone, 3-methylcyclopentanone,2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopentanone,cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone,4-ethylcyclohexanone, 2,2-dimethylcyclohexanone,2,6-dimethylcyclohexanone, 2,2,6-trimethylcyclohexanone, cycloheptanone,2-methylcycloheptanone, 3-methylcycloheptanone, pylene carbonate,vinylene carbonate, ethylene carbonate, and butylene carbonate,acetate-2-methoxyethyl, acetate-2-ethoxyethyl,acetate-2-(2-ethoxyethoxy)ethyl, acetate-3-methoxy-3-methylbutyl,acetate-1-methoxy-2-propyl, dipropylene glycol, monomethylether,monoethylether, monopropylether, monobutylehter, monopheylether,dipropylene glycol monoacetate, dioxane, etheyl lactate, methyl acetate,ethyl acetate, butyl acetate, methyl puruvate, ethyl puruvate, propylpyruvate, methyl methoxypropionate, ethyl ethoxypropionate,n-methylpyrrolidone (NMP), 2-methoxyethyl ether (diglyme), ethyleneglycol monom-ethyl ether, propylene glycol monomethyl ether; methylproponiate, ethyl proponiate and ethyl ethoxy proponiate, methylethylketone, cyclohexanone, 2-heptanone, carbon dioxide, cyclopentatone,cyclohexanone, ethyl 3-ethocypropionate, propylene glycol methyl etheracetate (PGMEA), methylene cellosolve, butyle acetate, and2-ethoxyethanol, N-methylformamide, N,N-dimethylformamide,N-methylformanilide, N-methylacetamide, N,N-dimethylacetamide,N-methylpyrrolidone, dimethylsulfoxide, benzyl ethyl ether, dihexylether, acetonylacetone, isophorone, caproic acid, caprylic acid,1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate,diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate,propylene carbonate, phenyl cellosolve acetate, or the like.

However, as one of ordinary skill in the art will recognize, thematerials listed and described above as examples of materials that maybe utilized for the photoresist solvent component of the photoresist 401are merely illustrative and are not intended to limit the embodiments.Rather, any suitable material that may dissolve the photoresist polymerresin and the PACs may alternatively be utilized to help mix and applythe photoresist 401. All such materials are fully intended to beincluded within the scope of the embodiments.

Additionally, while individual ones of the above described materials maybe used as the photoresist solvent for the photoresist 401, inalternative embodiments more than one of the above described materialsmay be utilized. For example, the photoresist solvent may comprise acombination mixture of two or more of the materials described. All suchcombinations are fully intended to be included within the scope of theembodiments.

Optionally, a photoresist cross-linking agent may also be added to thephotoresist 401. The photoresist cross-linking agent reacts with thephotoresist polymer resin within the photoresist 401 after exposure,assisting in increasing the cross-linking density of the photoresist,which helps to improve the resist pattern and resistance to dry etching.In an embodiment the photoresist cross-linking agent may be an melaminebased agent, a urea based agent, ethylene urea based agent, propyleneurea based agent, glycoluril based agent, an aliphatic cyclichydrocarbon having a hydroxyl group, a hydroxyalkyl group, or acombination of these, oxygen containing derivatives of the aliphaticcyclic hydrocarbon, glycoluril compounds, etherified amino resins,combinations of these, or the like.

Specific examples of materials that may be utilized as a photoresistcross-linking agent include melamine, acetoguanamine, benzoguanamine,urea, ethylene urea, or glycoluril with formaldehyde, glycoluril with acombination of formaldehyde and a lower alcohol,hexamethoxymethylmelamine, bismethoxymethylurea,bismethoxymethylbismethoxyethylene urea, tetramethoxymethylglycoluril,and tetrabutoxymethylglycoluril, mono-, di-, tri-, ortetra-hydroxymethylated glycoluril, mono-, di-, tri-, and/ortetra-methoxymethylated glycoluril, mono-, di-, tri-, and/ortetra-ethoxymethylated glycoluril, mono-, di-, tri-, and/ortetra-propoxymethylated glycoluril, and mono-, di-, tri-, and/ortetra-butoxymethylated glycoluril,2,3-dihydroxy-5-hydroxymethylnorbornane,2-hydroy-5,6-bis(hydroxymethyl)norbornane, cyclohexanedimethanol,3,4,8(or 9)-trihydroxytricyclodecane, 2-methyl-2-adamantanol,1,4-dioxane-2,3-diol and 1,3,5-trihydroxycyclohexane, tetramethoxymethylglycoluril, methylpropyltetramethoxymethyl glycoluril, andmethylphenyltetramethoxymethylglycoluril,2,6-bis(hydroxymethyl)p-cresol, N-methoxymethyl- orN-butoxymethyl-melamine. Additionally, compounds obtained by reactingformaldehyde, or formaldehyde and lower alcohols with aminogroup-containing compounds, such as melamine, acetoguanamine,benzoguanamine, urea, ethylene urea and glycoluril, and substituting thehydrogen atoms of the amino group with hydroxymethyl group or loweralkoxymethyl group, examples being hexamethoxymethylmelamine,bismethoxymethyl urea, bismethoxymethylbismethoxyethylene urea,tetramethoxymethyl glycoluril and tetrabutoxymethyl glycoluril,copolymers of 3-chloro-2-hydroxypropyl methacrylate and methacrylicacid, copolymers of 3-chloro-2-hydroxypropyl methacrylate and cyclohexylmethacrylate and methacrylic acid, copolymers of3-chloro-2-hydroxypropyl methacrylate and benzyl methacrylate andmethacrylic acid, bisphenol A-di(3-chloro-2-hydroxypropyl)ether,poly(3-chloro-2-hydroxypro-pyl)ether of a phenol novolak resin,pentaerythritol tetra(3-chloro-2-hydroxypropyl)ether, trimethylolmethanetri(3-chloro-2-hydroxypropyl)ether phenol, bisphenolA-di(3-acetoxy-2-hydroxypropyl)ether,poly(3-acetoxy-2-hydroxypropyl)ethe-r of a phenol novolak resin,pentaerythritol tetra(3-acetoxy-2-hydroxyprop-yl)ether, pentaerythritolpoly(3-chloroacetoxy-2-hydroxypropyl)ether, trimethylolmethanetri(3-acetoxy-2-hydroxypropyl)ether, combinations of these, or the like.

In addition to the photoresist polymer resins, the PACs, the photoresistsolvents, and the photoresist cross-linking agents, the photoresist 401may also include a number of other additives that will assist thephotoresist 401 obtain the highest resolution. For example, thephotoresist 401 may also include surfactants in order to help improvethe ability of the photoresist 401 to coat the surface on which it isapplied. In an embodiment the surfactants may include nonionicsurfactants, polymers having fluorinated aliphatic groups, surfactantsthat contain at least one fluorine atom and/or at least one siliconatom, polyoxyethylene alkyl ethers, polyoxyethylene alkyl aryl ethers,polyoxyethylene-polyoxypropylene block copolymers, sorbitan fatty acidesters, polyoxyethylene sorbitan fatty acid esters.

Specific examples of materials that may be used as surfactants includepolyoxyethylene lauryl ether, polyoxyethylene stearyl ether,polyoxyethylene cetyl ether, polyoxyethylene oleyl ether,polyoxyethylene octyl phenol ether, polyoxyethylene nonyl phenol ether,sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate,sorbitan monooleate, sorbitan trioleate, sorbitan tristearate,polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitanmonopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylenesorbitan trioleate, polyoxyethylene sorbitan tristearate, polyethyleneglycol distearate, polyethylene glycol dilaurate, polyethylene glycol,polypropylene glycol, polyoxyethylenestearyl ether and polyoxyethylenecetyl ether; fluorine containing cationic surfactants, fluorinecontaining nonionic surfactants, fluorine containing anionicsurfactants, cationic surfactants and anionic surfactants, combinationsof these, or the like.

Another additive that may be added to the photoresist 401 is a quencher,which may be utilized to inhibit diffusion of the generatedacids/bases/free radicals within the photoresist, which helps the resistpattern configuration as well as to improve the stability of thephotoresist 401 over time. In an embodiment the quencher is an aminesuch as a second lower aliphatic amine, a tertiary lower aliphaticamine, or the like. Specific examples of amines that may be used includetrimethylamine, diethylamine, triethylamine, di-n-propylamine,tri-n-propylamine, tripentylamine, diethanolamine, and triethanolamine,alkanolamine, combinations of these, or the like.

Alternatively, an organic acid may be utilized as the quencher. Specificembodiments of organic acids that may be utilized include malonic acid,citric acid, malic acid, succinic acid, benzoic acid, salicylic acid,phosphorous oxo acid and its derivatives such as phosphoric acid andderivatives thereof such as its esters, such as phosphoric acid,phosphoric acid di-n-butyl ester and phosphoric acid diphenyl ester;phosphonic acid and derivatives thereof such as its ester, such asphosphonic acid, phosphonic acid dimethyl ester, phosphonic aciddi-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester,and phosphonic acid dibenzyl ester; and phosphinic acid and derivativesthereof such as its esters, including phosphinic acid andphenylphosphinic acid.

Another additive that may be added to the photoresist 401 is astabilizer, which assists in preventing undesired diffusion of the acidsgenerated during exposure of the photoresist 401. In an embodiment thestabilizer may include nitrogenous compounds such as aliphatic primary,secondary, and tertiary amines, cyclic amines such as piperidines,pyrrolidines, morpholines, aromatic heterocycles such as pyridines,pyrimidines, purines, imines such as diazabicycloundecene, guanidines,imides, amides, and others. Alternatively, ammonium salts may also beused for the stabilizer, including ammonium, primary, secondary,tertiary, and quaternary alkyl- and arylammonium salts of alkoxidesincluding hydroxide, phenolates, carboxylates, aryl and alkylsulfonates, sulfonamides, and others. Other cationic nitrogenouscompounds including pyridinium salts and salts of other heterocyclicnitrogenous compounds with anions such as alkoxides including hydroxide,phenolates, carboxylates, aryl and alkyl sulfonates, sulfonamides, andthe like may also be employed.

Yet another additive that may be added to the photoresist 401 may be adissolution inhibitor in order to help control dissolution of thephotoresist 401 during development. In an embodiment bile-salt estersmay be utilized as the dissolution inhibitor. Specific examples ofmaterials that may be utilized include cholic acid (IV), deoxycholicacid (V), lithocholic acid (VI), t-butyl deoxycholate (VII), t-butyllithocholate (VIII), and t-butyl-3-α-acetyl lithocholate (IX).

Another additive that may be added to the photoresist 401 may be aplasticizer. Plasticizers may be used to reduce delamination andcracking between the photoresist 401 and underlying layers (e.g., theBARC layer 105) and may comprise monomeric, oligomeric, and polymericplasticizers such as oligo- and polyethyleneglycol ethers,cycloaliphatic esters, and non-acid reactive steroidally-derivedmaterials. Specific examples of materials that may be used for theplasticizer include dioctyl phthalate, didodecyl phthalate, triethyleneglycol dicaprylate, dimethyl glycol phthalate, tricresyl phosphate,dioctyl adipate, dibutyl sebacate, triacetyl glycerine and the like.

Yet another additive that may be added include a coloring agent, whichhelps observers examine the photoresist 401 and find any defects thatmay need to be remedied prior to further processing. In an embodimentthe coloring agent may be either a triarylmethane dye or, alternatively,may be a fine particle organic pigment. Specific examples of materialsthat may be used as coloring agents include crystal violet, methylviolet, ethyl violet, oil blue #603, Victoria Pure Blue BOH, malachitegreen, diamond green, phthalocyanine pigments, azo pigments, carbonblack, titanium oxide, brilliant green dye (C. I. 42020), Victoria PureBlue FGA (Linebrow), Victoria BO (Linebrow) (C. I. 42595), Victoria BlueBO (C. I. 44045) rhodamine 6G (C. I. 45160), Benzophenone compounds suchas 2,4-dihydroxybenzophenone and 2,2′,4,4′-tetrahydroxybenzophenone,salicylic acid compounds such as phenyl salicylate and 4-t-butylphenylsalicylate, phenylacrylate compounds such asethyl-2-cyano-3,3-diphenylacrylate, and2′-ethylhexyl-2-cyano-3,3-diphenylacrylate, benzotriazole compounds suchas 2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole, and2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole,coumarin compounds such as 4-methyl-7-diethylamino-1-benzopyran-2-one,thioxanthone compounds such as diethylthioxanthone, stilbene compounds,naphthalic acid compounds, azo dyes, Phthalocyanine blue, phthalocyaninegreen, iodine green, Victoria blue, naphthalene black, Photopia methylviolet, bromphenol blue and bromcresol green, laser dyes such asRhodamine G6, Coumarin 500, DCM(4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H pyran)),Kiton Red 620, Pyrromethene 580, or the like. Additionally, one or morecoloring agents may be used in combination to provide the desiredcoloring.

Adhesion additives may also be added to the photoresist 401 in order topromote adhesion between the photoresist 401 and an underlying layerupon which the photoresist 401 has been applied (e.g., the BARC layer105). In an embodiment the adhesion additives include a silane compoundwith at least one reactive substituent such as a carboxyl group, amethacryloyl group, an isocyanate group and/or an epoxy group. Specificexamples of the adhesion components include trimethoxysilyl benzoicacid, γ-methacryloxypropyl trimethoxy silane, vinyltriacetoxysilane,vinyltrimethoxysilane, γ-isocyanatepropyl triethoxy silane,γ-glycidoxypropyl trimethoxy silane, β-(3,4-epoxycyclohexyl)ethyltrimethoxy silane, benzimidazoles and polybenzimidazoles, a lowerhydroxyalkyl substituted pyridine derivative, a nitrogen heterocycliccompound, urea, thiourea, 8-oxyquinoline, 4-hydroxypteridine andderivatives, 1,10-phenanthroline and derivatives, 2,2′-bipyridine andderivatives, benzotriazoles; organophosphorus compounds,phenylenediamine compounds, 2-amino-1-phenylethanol,N-phenylethanolamine, N-ethyldiethanolamine, N-ethylethanolamine andderivatives, benzothiazole, and a benzothiazoleamine salt having acyclohexyl ring and a morpholine ring,3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane,3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane,3-methacryloyloxypropyltrimethoxysilane, vinyl trimethoxysilane,combinations of these, or the like.

Surface leveling agents may additionally be added to the photoresist 401in order to assist a top surface of the photoresist 401 to be level sothat impinging light will not be adversely modified by an unlevelsurface. In an embodiment surface leveling agents may includefluoroaliphatic esters, hydroxyl terminated fluorinated polyethers,fluorinated ethylene glycol polymers, silicones, acrylic polymerleveling agents, combinations of these, or the like.

In an embodiment the photoresist polymer resin and the PACs, along withany desired additives or other agents, are added to the photoresistsolvent for application. Once added, the mixture is then mixed in orderto achieve an even composition throughout the photoresist 401 in orderto ensure that there are no defects caused by an uneven mixing ornon-constant composition of the photoresist 401. Once mixed together,the photoresist 401 may either be stored prior to its usage or else usedimmediately.

Once ready, the photoresist 401 may be utilized by initially applyingthe photoresist 401 onto the BARC layer 105. The photoresist 401 may beapplied to the BARC layer 105 so that the photoresist 401 coats an upperexposed surface of the BARC layer 105, and may be applied using aprocess such as a spin-on coating process, a dip coating method, anair-knife coating method, a curtain coating method, a wire-bar coatingmethod, a gravure coating method, a lamination method, an extrusioncoating method, combinations of these, or the like. In an embodiment thephotoresist 401 may be applied such that it has a thickness over thesurface of the BARC layer 105 of between about 10 nm and about 300 nm,such as about 150 nm.

Once the photoresist 401 has been applied to the semiconductorsubstrate, a pre-bake of the photoresist 401 is performed in order tocure and dry the photoresist 401 prior to exposure to finish theapplication of the photoresist 401. The curing and drying of thephotoresist 401 removes the photoresist solvent component while leavingbehind the photoresist polymer resin, the PACs, photoresistcross-linking agents, and the other chosen additives. In an embodimentthe pre-bake may be performed at a temperature suitable to evaporate thephotoresist solvent, such as between about 40° C. and 150° C., althoughthe precise temperature depends upon the materials chosen for thephotoresist 401. The pre-bake is performed for a time sufficient to cureand dry the photoresist 401, such as between about 10 seconds to about 5minutes, such as about 90 seconds.

Once applied, the photoresist 401 may be exposed to form an exposedregion 403 and an unexposed region 405 within the photoresist 401. In anembodiment the exposure may be initiated by placing the substrate 101and the photoresist 401, once cured and dried, into a photoresistimaging device 400 for exposure. The photoresist imaging device 400 maycomprise a photoresist support plate 404, a photoresist energy source407, a patterned mask 409 between the photoresist support plate 404 andthe photoresist energy source 407, and photoresist optics 413. In anembodiment the photoresist support plate 404 is a surface to which thesemiconductor device 100 and the photoresist 401 may be placed orattached to and which provides support and control to the substrate 101during exposure of the photoresist 401. Additionally, the photoresistsupport plate 404 may be movable along one or more axes, as well asproviding any desired heating or cooling to the substrate 101 andphotoresist 401 in order to prevent temperature gradients from affectingthe exposure process.

In an embodiment the photoresist energy source 407 supplies photoresistenergy 411 such as light to the photoresist 401 in order to induce areaction of the PACs, which in turn reacts with the photoresist polymerresin to chemically alter those portions of the photoresist 401 to whichthe photoresist energy 411 impinges. In an embodiment the photoresistenergy 411 may be electromagnetic radiation, such as g-rays (with awavelength of about 436 nm), i-rays (with a wavelength of about 365 nm),ultraviolet radiation, far ultraviolet radiation, x-rays, electronbeams, or the like. The photoresist energy source 407 may be a source ofthe electromagnetic radiation, and may be a KrF excimer laser light(with a wavelength of 248 nm), an ArF excimer laser light (with awavelength of 193 nm), a F₂ excimer laser light (with a wavelength of157 nm), or the like, although any other suitable source of photoresistenergy 411, such as mercury vapor lamps, xenon lamps, carbon arc lampsor the like, may alternatively be utilized.

The patterned mask 409 is located between the photoresist energy source407 and the photoresist 401 in order to block portions of thephotoresist energy 411 to form a patterned energy 415 prior to thephotoresist energy 411 actually impinging upon the photoresist 401. Inan embodiment the patterned mask 409 may comprise a series of layers(e.g., substrate, absorbance layers, anti-reflective coating layers,shielding layers, etc.) to reflect, absorb, or otherwise block portionsof the photoresist energy 411 from reaching those portions of thephotoresist 401 which are not desired to be illuminated. The desiredpattern may be formed in the patterned mask 409 by forming openingsthrough the patterned mask 409 in the desired shape of illumination.

Optics (represented in FIG. 4A by the trapezoid labeled 413) may be usedto concentrate, expand, reflect, or otherwise control the photoresistenergy 411 as it leaves the photoresist energy source 407, is patternedby the patterned mask 409, and is directed towards the photoresist 401.In an embodiment the photoresist optics 413 comprise one or more lenses,mirrors, filters, combinations of these, or the like to control thephotoresist energy 411 along its path. Additionally, while thephotoresist optics 413 are illustrated in FIG. 4A as being between thepatterned mask 409 and the photoresist 401, elements of the photoresistoptics 413 (e.g., individual lenses, mirrors, etc.) may also be locatedat any location between the photoresist energy source 407 (where thephotoresist energy 411 is generated) and the photoresist 401.

In an embodiment the semiconductor device 100 with the photoresist 401is placed on the photoresist support plate 404. Once the pattern hasbeen aligned to the semiconductor device 100, the photoresist energysource 407 generates the desired photoresist energy 411 (e.g., light)which passes through the patterned mask 409 and the photoresist optics413 on its way to the photoresist 401. The patterned energy 415impinging upon portions of the photoresist 401 induces a reaction of thePACs within the photoresist 401. The chemical reaction products of thePACs' absorption of the patterned energy 415 (e.g., acids/bases/freeradicals) then reacts with the photoresist polymer resin, chemicallyaltering the photoresist 401 in those portions that were illuminatedthrough the patterned mask 409.

In a specific example in which the patterned energy 415 is a 193 nmwavelength of light, the PAC is a photoacid generator, and the group tobe decomposed is a carboxylic acid group on the hydrocarbon structureand a cross linking agent is used, the patterned energy 415 will impingeupon the photoacid generator and the photoacid generator will absorb theimpinging patterned energy 415. This absorption initiates the photoacidgenerator to generate a proton (e.g., a H+ ion) within the photoresist401. When the proton impacts the carboxylic acid group on thehydrocarbon structure, the proton will react with the carboxylic acidgroup, chemically altering the carboxylic acid group and altering theproperties of the photoresist polymer resin in general. The carboxylicacid group will then react with the photoresist cross-linking agent tocross-link with other photoresist polymer resins within the photoresist401.

Optionally, the exposure of the photoresist 401 may occur using animmersion lithography technique. In such a technique an immersion medium(not individually illustrated in FIG. 2) may be placed between thephotoresist imaging device 400 (and particularly between a final lens ofthe photoresist optics 413) and the photoresist 401. With this immersionmedium in place, the photoresist 401 may be patterned with the patternedenergy 415 passing through the immersion medium.

In this embodiment a protective layer (also not individually illustratedin FIG. 4A) may be formed over the photoresist 401 in order to preventthe immersion medium from coming into direct contact with thephotoresist 401 and leaching or otherwise adversely affecting thephotoresist 401. In an embodiment the protective layer is insolublewithin the immersion medium such that the immersion medium will notdissolve it and is immiscible in the photoresist 401 such that theprotective layer will not adversely affect the photoresist 401.Additionally, the protective layer is transparent so that the patternedenergy 415 may pass through the protective layer without hindrance.

In an embodiment the protective layer comprises a protective layer resinwithin a protective layer solvent. The material used for the protectivelayer solvent is, at least in part, dependent upon the components chosenfor the photoresist 401, as the protective layer solvent should notdissolve the materials of the photoresist 401 so as to avoid degradationof the photoresist 401 during application and use of the protectivelayer. In an embodiment the protective layer solvent includes alcoholsolvents, fluorinated solvents, and hydrocarbon solvents.

Specific examples of materials that may be utilized for the protectivelayer solvent include methanol, ethanol, 1-propanol, isopropanol,n-propanol, 1-butanol, 2-butanol, 2-methyl-2-propanol,3-methyl-1-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol,2-pentanol, 3-pentanol, n-hexanol, cyclohecanol, 1-hexanol, 1-heptanol,1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol,3-octanol, 4-octanol, 2-methyl-2-butanol, 3-methyl-1-butanol,3-methyl-2-butanol, 2-methyl-1-butanol, 2-methyl-1-pentanol,2-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-1-pentanol,3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol,4-methyl-2-pentanol, 2,2,3,3,4,4-hexafluoro-1-butanol,2,2,3,3,4,4,5,5-octafluoro-1-pentanol,2,2,3,3,4,4,5,5,6,6-decafluoro-1-hexanol,2,2,3,3,4,4-hexafluoro-1,5-pentanediol,2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol,2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoro-1,8-diol, 2-fluoroanisole,2,3-difluoroanisole, perfluorohexane, perfluoroheptane,perfluoro-2-pentanone, perfluoro-2-butyltetrahydrofuran,perfluorotetrahydrofuran, perfluorotributylamine,perfluorotetrapentylamine, toluene, xylene and anisole, and aliphatichydrocarbon solvents, such as n-heptane, n-nonane, n-octane, n-decane,2-methylheptane, 3-methylheptane, 3,3-dimethylhexane,2,3,4-trimethylpentane, combinations of these, or the like.

The protective layer resin may, similar to the photoresist 401, comprisea protective layer repeating unit. In an embodiment the protective layerrepeating unit may be an acrylic resin with a repeating hydrocarbonstructure having a carboxyl group, an alicyclic structure, an alkylgroup having one to five carbon atoms, a phenol group, or a fluorineatom-containing group. Specific examples of the alicyclic structureinclude a cyclohexyl group, an adamantyl group, a norbornyl group, aisobornyl group, a tricyclodecyl group, a tetracyclododecyl group, andthe like. Specific examples of the alkyl group include an n-butyl group,an isobutyl group, or the like. However, any suitable protective layerresin may alternatively be utilized.

The protective layer composition may also include additional additivesto assist in such things as adhesion, surface leveling, coating, and thelike. For example, the protective layer composition may further comprisea protective layer surfactant, although other additives may also beadded, and all such additions are fully intended to be included withinthe scope of the embodiment. In an embodiment the protective layersurfactant may be an alkyl cationic surfactant, an amide-type quaternarycationic surfactant, an ester-type quaternary cationic surfactant, anamine oxide surfactant, a betaine surfactant, an alkoxylate surfactant,a fatty acid ester surfactant, an amide surfactant, an alcoholsurfactant, an ethylenediamine surfactant, or a fluorine- and/orsilicon-containing surfactant.

Specific examples of materials that may be used for the protective layersurfactant include polyoxyethylene alkyl ethers, such as polyoxyethylenelauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl etherand polyoxyethylene oleyl ether; polyoxyethylene alkyl aryl ethers, suchas polyoxyethylene octyl phenol ether and polyoxyethylene nonyl phenolether; polyoxyethylene-polyooxypropylene block copolymers; sorbitanfatty acid esters, such as sorbitan monolaurate, sorbitan monopalmitate,sorbitan monostearate, sorbitan monooleate, sorbitan trioleate andsorbitan tristearate; and polyoxyethylene sorbitan monolaurate,polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitanmonostearate, polyoxyethylene sorbitan trioleate and polyoxyethylenesorbitan tristearate.

Prior to application of the protective layer onto the photoresist 401,the protective layer resin and desired additives are first added to theprotective layer solvent to form a protective layer composition. Theprotective layer solvent is then mixed to ensure that the protectivelayer composition has a consistent concentration throughout theprotective layer composition.

Once the protective layer composition is ready for application, theprotective layer composition may be applied over the photoresist 401. Inan embodiment the application may be performed using a process such as aspin-on coating process, a dip coating method, an air-knife coatingmethod, a curtain coating method, a wire-bar coating method, a gravurecoating method, a lamination method, an extrusion coating method,combinations of these, or the like. In an embodiment the protectivelayer composition may be applied such that it has a thickness over thesurface of the photoresist 401 of about 100 nm.

After the protective layer composition has been applied to thephotoresist 401, a protective layer pre-bake may be performed in orderto remove the protective layer solvent. In an embodiment the protectivelayer pre-bake may be performed at a temperature suitable to evaporatethe protective layer solvent, such as between about 40° C. and 150° C.,although the precise temperature depends upon the materials chosen forthe protective layer composition. The protective layer pre-bake isperformed for a time sufficient to cure and dry the protective layercomposition, such as between about 10 seconds to about 5 minutes, suchas about 90 seconds.

Once the protective layer has been placed over the photoresist 401, thesemiconductor device 100 with the photoresist 401 and the protectivelayer are placed on the photoresist support plate 404, and the immersionmedium may be placed between the protective layer and the photoresistoptics 413. In an embodiment the immersion medium is a liquid having arefractive index greater than that of the surrounding atmosphere, suchas having a refractive index greater than 1. Examples of the immersionmedium may include water, oil, glycerine, glycerol, cycloalkanols, orthe like, although any suitable medium may alternatively be utilized.

The placement of the immersion medium between the protective layer andthe photoresist optics 413 may be done using, e.g., an air knife method,whereby fresh immersion medium is applied to a region between theprotective layer and the photoresist optics 413 and controlled usingpressurized gas directed towards the protective layer to form a barrierand keep the immersion medium from spreading. In this embodiment theimmersion medium may be applied, used, and removed from the protectivelayer for recycling so that there is fresh immersion medium used for theactual imaging process.

However, the air knife method described above is not the only method bywhich the photoresist 401 may be exposed using an immersion method. Anyother suitable method for imaging the photoresist 401 using an immersionmedium, such as immersing the entire substrate 101 along with thephotoresist 401 and the protective layer, using solid barriers insteadof gaseous barriers, or using an immersion medium without a protectivelayer, may also be utilized. Any suitable method for exposing thephotoresist 401 through the immersion medium may be used, and all suchmethods are fully intended to be included within the scope of theembodiments.

After the photoresist 401 has been exposed to the patterned energy 415,a post-exposure baking may be used in order to assist in the generating,dispersing, and reacting of the acid/base/free radical generated fromthe impingement of the patterned energy 415 upon the PACs during theexposure. Such assistance helps to create or enhance chemical reactionswhich generate chemical differences between the exposed region 403 andthe unexposed region 405 within the photoresist 401. These chemicaldifferences also caused differences in the solubility between theexposed region 403 and the unexposed region 405. In an embodiment thispost-exposure baking may occur at temperatures of between about 50° C.and about 160° C. for a period of between about 40 seconds and about 120seconds.

FIG. 4B illustrates a development of the photoresist 401 with the use ofa developer 417 after the photoresist 401 has been exposed. After thephotoresist 401 has been exposed and the post-exposure baking hasoccurred, the photoresist 401 may be developed using either a positivetone developer or a negative tone developer, depending upon the desiredpattern for the photoresist 401. In an embodiment in which the exposedregion 403 of the photoresist 401 is desired to be removed to form apositive tone, a positive tone developer such as a basic aqueoussolution may be utilized to remove those portions of the photoresist 401which were exposed to the patterned energy 415 and which have had theirsolubility modified and changed through the chemical reactions. Suchbasic aqueous solutions may include tetra methyl ammonium hydroxide(TMAH), tetra butyl ammonium hydroxide, sodium hydroxide, potassiumhydroxide, sodium carbonate, sodium bicarbonate, sodium silicate, sodiummetasilicate, aqueous ammonia, monomethylamine, dimethylamine,trimethylamine, monoethylamine, diethylamine, triethylamine,monoisopropylamine, diisopropylamine, triisopropylamine, monobutylamine,dibutylamine, monoethanolamine, diethanolamine, triethanolamine,dimethylaminoethanol, diethylaminoethanol, potassium metasilicate,sodium carbonate, tetraethylammonium hydroxide, combinations of these,or the like.

If a negative tone development is desired, an organic solvent orcritical fluid may be utilized to remove those portions of thephotoresist 401 which were not exposed to the energy and, as such,retain their original solubility. Specific examples of materials thatmay be utilized include hydrocarbon solvents, alcohol solvents, ethersolvents, ester solvents, critical fluids, combinations of these, or thelike. Specific examples of materials that can be used for the negativetone solvent include hexane, heptane, octane, toluene, xylene,dichloromethane, chloroform, carbon tetrachloride, trichloroethylene,methanol, ethanol, propanol, butanol, critical carbon dioxide, diethylether, dipropyl ether, dibutyl ether, ethyl vinyl ether, dioxane,propylene oxide, tetrahydrofuran, cellosolve, methyl cellosolve, butylcellosolve, methyl carbitol, diethylene glycol monoethyl ether, acetone,methyl ethyl ketone, methyl isobutyl ketone, isophorone, cyclohexanone,methyl acetate, ethyl acetate, propyl acetate, butyl acetate, pyridine,formamide, N,N-dimethyl formamide, or the like.

However, as one of ordinary skill in the art will recognize, the abovedescription of positive tone developers and negative tone developers areonly intended to be illustrative and are not intended to limit theembodiments to only the developers listed above. Rather, any suitabletype of developer, including acid developers or even water developers,that may be utilized to selectively remove a portion of the photoresist401 that has a different property (e.g., solubility) than anotherportion of the photoresist 401, may alternatively be utilized, and allsuch developers are fully intended to be included within the scope ofthe embodiments.

In an embodiment in which immersion lithography is utilized to exposethe photoresist 401 and a protective layer is utilized to protect thephotoresist 401 from the immersion medium, the developer 417 may bechosen to remove not only those portions of the photoresist 401 that aredesired to be removed, but may also be chosen to remove the protectivelayer in the same development step. Alternatively, the protective layermay be removed in a separate process, such as by a separate solvent fromthe developer 417 or even an etching process to remove the protectivelayer from the photoresist 401 prior to development.

FIG. 4B illustrates an application of the developer 417 to thephotoresist 401 using, e.g., a spin-on process. In this process thedeveloper 417 is applied to the photoresist 401 from above thephotoresist 401 while the semiconductor device 100 (and the photoresist401) is rotated. In an embodiment the developer 417 may be supplied at aflow rate of between about 300 mL/min and about 1000 mL/min, such asabout 500 mL/min, while the semiconductor device 100 is being rotated ata speed of between about 500 rpm and about 2500 rpm, such as about 1500rpm. In an embodiment the developer 417 may be at a temperature ofbetween about 10° C. and about 80° C., such as about 50° C., and thedevelopment may continue for between about 1 minute to about 60 minutes,such as about 30 minutes.

However, while the spin-on method described herein is one suitablemethod for developing the photoresist 401 after exposure, it is intendedto be illustrative and is not intended to limit the embodiments. Rather,any suitable method for development, including dip processes, puddleprocesses, spray-on processes, combinations of these, or the like, mayalternatively be used. All such development processes are fully intendedto be included within the scope of the embodiments.

FIG. 4B illustrates a cross-section of the development process in anembodiment in which a negative tone developer is used to remove theunexposed regions of the photoresist 401. As illustrated, the developer417 is applied to the photoresist 401 and dissolves the unexposedportion 405 of the photoresist 401. This dissolving and removing of theunexposed portion 405 of the photoresist 401 leaves behind an openingwithin the photoresist 401 that patterns the photoresist 401 in theshape of the patterned energy 415, thereby transferring the pattern ofthe patterned mask 409 to the photoresist 401.

Once the photoresist 401 has been patterned, the pattern may betransferred to the BARC layer 105. In an embodiment in which the BARClayer 105 remains insoluble to the developer 417, the BARC layer 105 maybe removed using an etching process that utilizes the photoresist 401(now patterned) as a masking layer. The etching process may be a dryetch process utilizing an etchant such as oxygen, nitrogen, hydrogen,ammonia, sulfur hexafluoride, difluoromethane, nitrogen trifluoride,chlorine trifluoride, chlorine, carbon monoxide, carbon dioxide, helium,boron dichloride, argon, fluorine, trifluoromethane, tetrafluoromethane,perfluorocyclobutane, perfluoropropane, combinations of these, or thelike. However, any other suitable etch process, such as a wet etch, andany other suitable etchants may alternatively be used.

Alternatively, in an embodiment in which the BARC layer 105 comprises anacid labile group that can react to de-crosslink the cross-linkedpolymers in the BARC layer 105 and change the solubility of the BARClayer 105, the BARC layer 105 may be patterned during the developmentprocess by the developer 417. In particular, during exposure thephotoacid generators may generate an acid in the BARC layer 105, whichwill work to break the cross-linking bonds and change the solubility ofthe BARC layer 105. Then, in a positive tone development process, apositive tone developer may be used to remove both the photoresist 417that had been exposed as well as to remove the BARC layer 105 in thesame process. Any suitable patterning process, with any suitable numberof steps, may be utilized to pattern and remove both the photoresist 417and the BARC layer 105, and all such processes and steps are fullyintended to be included within the scope of the embodiments.

FIG. 5 illustrates another embodiment in which the BARC layer 105 isutilized in a physical planarization process such as a chemicalmechanical polish (CMP). In a CMP process, a combination of etchingmaterials and abrading materials are put into contact with the BARClayer 105 (or a layer overlying the BARC layer 105, such as thephotoresist 401) and a grinding pad 501 is used to grind away the BARClayer 105 (or any layers overlying the BARC layer 105) until a desiredthickness is achieved.

In this embodiment the floating region 201 along the top surface of theBARC layer 105 will cause the polymer resin to crosslink within thefloating region 201 more than within the remainder of the BARC layer105. As such, the remainder of the BARC layer 105 (that portion outsideof the floating region 201) will have a lower cross-linking density andwill remain more flexible than the floating region 201. This flexibilitycan better withstand the shear forces that are associated with thephysical grinding of the chemical mechanical polishing process without afailure such as peeling occurring.

In accordance with an embodiment, a method for manufacturing asemiconductor device comprising dispensing an anti-reflective materialover a substrate to form an anti-reflective coating layer, theanti-reflective material having a first concentration of a floatingcomponent is provided. A floating region is formed adjacent to a topsurface of the anti-reflective layer, the floating region having asecond concentration of the floating component greater than the firstconcentration.

In accordance with another embodiment, a method of manufacturing asemiconductor device comprising applying an anti-reflective coating ontoa substrate, the anti-reflective coating comprising at least onecomponent that has a fluorine atom, is provided. A floating region isformed along a top surface of the anti-reflective coating, wherein thefloating region has a higher concentration of the at least one componentthan the remainder of the anti-reflective coating. The anti-reflectivecoating is baked to initiate a cross-linking reaction in the floatingregion.

In accordance with yet another embodiment, an anti-reflective materialcomprising a polymer resin and a cross-linking agent is provided,wherein one of the polymer resin or the cross-linking agent comprises afluorine atom. The anti-reflective material also comprises a catalyst.

Although the present embodiments and their advantages have beendescribed in detail, it should be understood that various changes,substitutions and alterations can be made herein without departing fromthe spirit and scope of the disclosure as defined by the appendedclaims. For example, many different monomers may be used to form thematerial of the BARC layer, and may different processes may be utilizedto form, apply, and develop the photoresist.

Moreover, the scope of the present application is not intended to belimited to the particular embodiments of the process, machine,manufacture, composition of matter, means, methods and steps describedin the specification. As one of ordinary skill in the art will readilyappreciate from the disclosure, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed, that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized according to the present disclosure.Accordingly, the appended claims are intended to include within theirscope such processes, machines, manufacture, compositions of matter,means, methods, or steps.

What is claimed is:
 1. A method of manufacturing a semiconductor device,the method comprising: applying an anti-reflective coating onto asubstrate, the anti-reflective coating comprising a first component anda second component, wherein prior to the applying the anti-reflectivecoating the first component has a constant concentration within theanti-reflective coating; and forming a first region and a second regionwithin the anti-reflective coating, wherein the first region comprises afirst concentration of the first component and a second concentration ofthe second component and wherein the second region comprises a thirdconcentration of the first component and the second concentration of thesecond component, wherein the first concentration is at least 0.01% andthe third concentration is different from the first concentration. 2.The method of claim 1, further comprising initiating a cross-linkingwithin the first region after the forming the first region and thesecond region, wherein the second region has a first height prior to theinitiating the cross-linking and has the first height subsequent to theinitiating the cross-linking.
 3. The method of claim 1, wherein thefirst concentration is less than about 10%.
 4. The method of claim 3,wherein prior to the applying the anti-reflective coating onto thesubstrate the anti-reflective coating has a fourth concentration of thefirst component, the fourth concentration between about 0.01% and about30%.
 5. The method of claim 3, wherein the first concentration is lessthan about 5%.
 6. The method of claim 1, wherein the first region has athickness of at least 10 Å.
 7. The method of claim 1, further comprisinginitiating a cross-linking within the first region after the forming thefirst region and the second region, wherein the second region has afirst hydrophilicity prior to the initiating the cross-linking and hasthe first hydrophilicity after the initiating the cross-linking.
 8. Amethod of manufacturing a semiconductor device, the method comprising:forming fins located over a substrate; dispensing a bottomanti-reflective coating onto the fins, wherein the bottomanti-reflective coating is dispensed between the fins and comprises afirst concentration of a first component as the bottom anti-reflectivecoating is dispensed; and forming a floating region within the bottomanti-reflective coating, wherein the floating region has a thickness ofat least 10 Å and the first component has a second concentration largerthan the first concentration within the floating region than a regionoutside of the floating region, and wherein a second component differentfrom the first component has a constant concentration throughout boththe floating region and outside of the floating region.
 9. The method ofclaim 8, wherein the first concentration is between about 0.1% and about60%.
 10. The method of claim 8, wherein the first concentration isbetween about 0.01% and about 30%.
 11. The method of claim 10, whereinthe second concentration is between about 0.01 and about 10%.
 12. Themethod of claim 11, wherein the first component has a thirdconcentration outside of the floating region that is less than about 5%.13. The method of claim 8, further comprising initiating a cross-linkingreaction within the floating region after the forming the floatingregion, wherein the region outside of the floating region experiences noshrinkage during the cross-linking reaction.
 14. The method of claim 8,further comprising: placing a photoresist onto the floating region afterthe forming the floating region; and patterning the bottomanti-reflective coating after the placing the photoresist.
 15. A methodof manufacturing a semiconductor device, the method comprising:dispensing an anti-reflective material between a first fin and a secondfin, wherein the first fin and the second fin comprise semiconductormaterial; waiting until a first component within the anti-reflectivematerial forms a floating region with a thickness of at least 10 Åwithin the anti-reflective material, wherein the first component has aconcentration within the floating region of between about 0.01% to about10%; applying a photoresist over the floating region; and patterning theanti-reflective material while the photoresist is located over theanti-reflective material.
 16. The method of claim 15, wherein theanti-reflective material has a concentration of the first component ofbetween about 0.01% to about 30% prior to the dispensing theanti-reflective material.
 17. The method of claim 15, wherein thepatterning the anti-reflective material comprises applying a developerto the anti-reflective material.
 18. The method of claim 15, wherein thepatterning the anti-reflective material comprises an etching process.19. The method of claim 15, wherein the anti-reflective material has aconcentration of the first component of between about 0.01% to about 60%prior to the dispensing the anti-reflective material and wherein thefirst component is a floating polymer.
 20. The method of claim 15,wherein the first component has a concentration outside of the floatingregion of less than about 5%.